1400 câu trắc nghiệm Đọc hiểu Tiếng Anh có đáp án cực hay

Herman Melville, an American author best known today for his novel Moby Dick, was actually more popular during his lifetime for some of his other works. He traveled extensively and used the knowledge gained during his travels as the basis for his early novels. In 1837, at the age of eighteen, Melville signed as a cabin boy on a merchant ship that was to sail from his Massachusetts home to Liverpool, England. His experiences on this trip served as a basis for the novel Redburn (1849). In 1841 Melville set out on a whaling ship headed for the South Seas. After jumping ship in Tahiti, he wandered around the islands of Tahiti and Moorea. This South Sea island sojourn was a backdrop to the novel Omoo (1847). After three years away from home, Melville joined up with a U.S. naval frigate that was returning to the eastern United States around Cape Horn. The novel White-Jacket (1850) describes this lengthy voyage as a navy seaman.

With the publication of these early adventure novels, Melville developed a strong and loyal following among readers eager for his tales of exotic places and situations. However, in 1851, with the publication of Moby Dick, Melville's popularity started to diminish. Moby Dick, on one level the saga of the hunt for the great white whale, was also a heavily symbolic allegory of the heroic struggle of man against the universe. The public was not ready for Melville's literary metamorphosis from romantic adventure to philosophical symbolism. It is ironic that the novel that served to diminish Melville's popularity during his lifetime is the one for which he is best known today.

A. Melville’s travels

B. Moby Dick

C. Melville’s personal background

D. the popularity of Melville’s novels.

Herman Melville, an American author best known today for his novel Moby Dick, was actually more popular during his lifetime for some of his other works. He traveled extensively and used the knowledge gained during his travels as the basis for his early novels. In 1837, at the age of eighteen, Melville signed as a cabin boy on a merchant ship that was to sail from his Massachusetts home to Liverpool, England. His experiences on this trip served as a basis for the novel Redburn (1849). In 1841 Melville set out on a whaling ship headed for the South Seas. After jumping ship in Tahiti, he wandered around the islands of Tahiti and Moorea. This South Sea island sojourn was a backdrop to the novel Omoo (1847). After three years away from home, Melville joined up with a U.S. naval frigate that was returning to the eastern United States around Cape Horn. The novel White-Jacket (1850) describes this lengthy voyage as a navy seaman.

With the publication of these early adventure novels, Melville developed a strong and loyal following among readers eager for his tales of exotic places and situations. However, in 1851, with the publication of Moby Dick, Melville's popularity started to diminish. Moby Dick, on one level the saga of the hunt for the great white whale, was also a heavily symbolic allegory of the heroic struggle of man against the universe. The public was not ready for Melville's literary metamorphosis from romantic adventure to philosophical symbolism. It is ironic that the novel that served to diminish Melville's popularity during his lifetime is the one for which he is best known today.

A. background

B. message

C. bottom

D. dissertation

Herman Melville, an American author best known today for his novel Moby Dick, was actually more popular during his lifetime for some of his other works. He traveled extensively and used the knowledge gained during his travels as the basis for his early novels. In 1837, at the age of eighteen, Melville signed as a cabin boy on a merchant ship that was to sail from his Massachusetts home to Liverpool, England. His experiences on this trip served as a basis for the novel Redburn (1849). In 1841 Melville set out on a whaling ship headed for the South Seas. After jumping ship in Tahiti, he wandered around the islands of Tahiti and Moorea. This South Sea island sojourn was a backdrop to the novel Omoo (1847). After three years away from home, Melville joined up with a U.S. naval frigate that was returning to the eastern United States around Cape Horn. The novel White-Jacket (1850) describes this lengthy voyage as a navy seaman.

With the publication of these early adventure novels, Melville developed a strong and loyal following among readers eager for his tales of exotic places and situations. However, in 1851, with the publication of Moby Dick, Melville's popularity started to diminish. Moby Dick, on one level the saga of the hunt for the great white whale, was also a heavily symbolic allegory of the heroic struggle of man against the universe. The public was not ready for Melville's literary metamorphosis from romantic adventure to philosophical symbolism. It is ironic that the novel that served to diminish Melville's popularity during his lifetime is the one for which he is best known today.

A. published while he was traveling

B. completely fictional

C. all about his work on whaling ships

D. based on his travel experience

Herman Melville, an American author best known today for his novel Moby Dick, was actually more popular during his lifetime for some of his other works. He traveled extensively and used the knowledge gained during his travels as the basis for his early novels. In 1837, at the age of eighteen, Melville signed as a cabin boy on a merchant ship that was to sail from his Massachusetts home to Liverpool, England. His experiences on this trip served as a basis for the novel Redburn (1849). In 1841 Melville set out on a whaling ship headed for the South Seas. After jumping ship in Tahiti, he wandered around the islands of Tahiti and Moorea. This South Sea island sojourn was a backdrop to the novel Omoo (1847). After three years away from home, Melville joined up with a U.S. naval frigate that was returning to the eastern United States around Cape Horn. The novel White-Jacket (1850) describes this lengthy voyage as a navy seaman.

With the publication of these early adventure novels, Melville developed a strong and loyal following among readers eager for his tales of exotic places and situations. However, in 1851, with the publication of Moby Dick, Melville's popularity started to diminish. Moby Dick, on one level the saga of the hunt for the great white whale, was also a heavily symbolic allegory of the heroic struggle of man against the universe. The public was not ready for Melville's literary metamorphosis from romantic adventure to philosophical symbolism. It is ironic that the novel that served to diminish Melville's popularity during his lifetime is the one for which he is best known today.

A. he had unofficially left his ship

B. he was on leave while his ship was in port

C. he had finished his term of duty

D. he had received permission to take a vacation in Tahiti

Herman Melville, an American author best known today for his novel Moby Dick, was actually more popular during his lifetime for some of his other works. He traveled extensively and used the knowledge gained during his travels as the basis for his early novels. In 1837, at the age of eighteen, Melville signed as a cabin boy on a merchant ship that was to sail from his Massachusetts home to Liverpool, England. His experiences on this trip served as a basis for the novel Redburn (1849). In 1841 Melville set out on a whaling ship headed for the South Seas. After jumping ship in Tahiti, he wandered around the islands of Tahiti and Moorea. This South Sea island sojourn was a backdrop to the novel Omoo (1847). After three years away from home, Melville joined up with a U.S. naval frigate that was returning to the eastern United States around Cape Horn. The novel White-Jacket (1850) describes this lengthy voyage as a navy seaman.

With the publication of these early adventure novels, Melville developed a strong and loyal following among readers eager for his tales of exotic places and situations. However, in 1851, with the publication of Moby Dick, Melville's popularity started to diminish. Moby Dick, on one level the saga of the hunt for the great white whale, was also a heavily symbolic allegory of the heroic struggle of man against the universe. The public was not ready for Melville's literary metamorphosis from romantic adventure to philosophical symbolism. It is ironic that the novel that served to diminish Melville's popularity during his lifetime is the one for which he is best known today.

A. His popularity remained as strong as ever.

B. It caused his popularity to decrease.

C. His popularity increased immediately.

D. It had no effect on his popularity.

Herman Melville, an American author best known today for his novel Moby Dick, was actually more popular during his lifetime for some of his other works. He traveled extensively and used the knowledge gained during his travels as the basis for his early novels. In 1837, at the age of eighteen, Melville signed as a cabin boy on a merchant ship that was to sail from his Massachusetts home to Liverpool, England. His experiences on this trip served as a basis for the novel Redburn (1849). In 1841 Melville set out on a whaling ship headed for the South Seas. After jumping ship in Tahiti, he wandered around the islands of Tahiti and Moorea. This South Sea island sojourn was a backdrop to the novel Omoo (1847). After three years away from home, Melville joined up with a U.S. naval frigate that was returning to the eastern United States around Cape Horn. The novel White-Jacket (1850) describes this lengthy voyage as a navy seaman.

With the publication of these early adventure novels, Melville developed a strong and loyal following among readers eager for his tales of exotic places and situations. However, in 1851, with the publication of Moby Dick, Melville's popularity started to diminish. Moby Dick, on one level the saga of the hunt for the great white whale, was also a heavily symbolic allegory of the heroic struggle of man against the universe. The public was not ready for Melville's literary metamorphosis from romantic adventure to philosophical symbolism. It is ironic that the novel that served to diminish Melville's popularity during his lifetime is the one for which he is best known today.

A. symbolic of humanity fighting the universe

B. a single-faceted work

C. a short story about a whale

D. a 47 adventure

Herman Melville, an American author best known today for his novel Moby Dick, was actually more popular during his lifetime for some of his other works. He traveled extensively and used the knowledge gained during his travels as the basis for his early novels. In 1837, at the age of eighteen, Melville signed as a cabin boy on a merchant ship that was to sail from his Massachusetts home to Liverpool, England. His experiences on this trip served as a basis for the novel Redburn (1849). In 1841 Melville set out on a whaling ship headed for the South Seas. After jumping ship in Tahiti, he wandered around the islands of Tahiti and Moorea. This South Sea island sojourn was a backdrop to the novel Omoo (1847). After three years away from home, Melville joined up with a U.S. naval frigate that was returning to the eastern United States around Cape Horn. The novel White-Jacket (1850) describes this lengthy voyage as a navy seaman.

With the publication of these early adventure novels, Melville developed a strong and loyal following among readers eager for his tales of exotic places and situations. However, in 1851, with the publication of Moby Dick, Melville's popularity started to diminish. Moby Dick, on one level the saga of the hunt for the great white whale, was also a heavily symbolic allegory of the heroic struggle of man against the universe. The public was not ready for Melville's literary metamorphosis from romantic adventure to philosophical symbolism. It is ironic that the novel that served to diminish Melville's popularity during his lifetime is the one for which he is best known today.

A. 1849

B. 1837

C. 1847

D. 1841

Herman Melville, an American author best known today for his novel Moby Dick, was actually more popular during his lifetime for some of his other works. He traveled extensively and used the knowledge gained during his travels as the basis for his early novels. In 1837, at the age of eighteen, Melville signed as a cabin boy on a merchant ship that was to sail from his Massachusetts home to Liverpool, England. His experiences on this trip served as a basis for the novel Redburn (1849). In 1841 Melville set out on a whaling ship headed for the South Seas. After jumping ship in Tahiti, he wandered around the islands of Tahiti and Moorea. This South Sea island sojourn was a backdrop to the novel Omoo (1847). After three years away from home, Melville joined up with a U.S. naval frigate that was returning to the eastern United States around Cape Horn. The novel White-Jacket (1850) describes this lengthy voyage as a navy seaman.

With the publication of these early adventure novels, Melville developed a strong and loyal following among readers eager for his tales of exotic places and situations. However, in 1851, with the publication of Moby Dick, Melville's popularity started to diminish. Moby Dick, on one level the saga of the hunt for the great white whale, was also a heavily symbolic allegory of the heroic struggle of man against the universe. The public was not ready for Melville's literary metamorphosis from romantic adventure to philosophical symbolism. It is ironic that the novel that served to diminish Melville's popularity during his lifetime is the one for which he is best known today.

A. descent

B. circle

C. mysticism

D. change

Most people think that lions only come from Africa. This is understandable because in fact most lions do come from there but this has not always been the case. If we went back ten thousand years, we would find that there were lions roaming vast sections of the globe. However now, unfortunately only a very small section of the lion's former habitat remains. Asiatic lions are sub-species of African lions. It is almost a hundred thousand years since the Asiatic lions split off and developed as a sub-species. At one time the Asiatic lion was living as far west as Greece and they were found from there, but in a band that spreads east through various countries of the Middle East, all the way to India. In museums now, you can see Greek coins that have clear images of the Asiatic lion on them. Most of them are dated at around 500 B.C. However, Europe saw its last Asiatic lions roaming free two thousand years ago. Over the next nineteen hundred years the numbers of Asiatic lions in the other areas declined steadily, but it was only in the nineteenth century that they disappeared from everywhere but in India.

The Gir Wildlife Sanctuary in India was established especially to protect the Asiatic lion. There are now around three hundred Asiatic lions in India and almost all of them are in this sanctuary. However, despite living in a sanctuary, which makes them safe from hunters, they still face a number of problems that threaten their survival. One of these is the ever-present danger of disease. This is what killed more than a third of Africa’s Serengeti lions in 1994, and people are fearful that something similar could happen in the Gir Sanctuary and kill off many of the Asiatic lions there.

India's lions are particular vulnerable because they have a limited gene pool. The reason for this is interesting is because all of them are descended from a few dozen lions that were saved by a prince who took a particular interest in them. He was very healthy, and he managed to protect them; otherwise they would probably have died out completely. When you see the Asiatic lion in India, what you sense is enormous vitality. They are very impressive animals and you would never guess that they have this vulnerability when you look at them.

A. Africa

B. Europe

C. Middle East

D. India

Most people think that lions only come from Africa. This is understandable because in fact most lions do come from there but this has not always been the case. If we went back ten thousand years, we would find that there were lions roaming vast sections of the globe. However now, unfortunately only a very small section of the lion's former habitat remains. Asiatic lions are sub-species of African lions. It is almost a hundred thousand years since the Asiatic lions split off and developed as a sub-species. At one time the Asiatic lion was living as far west as Greece and they were found from there, but in a band that spreads east through various countries of the Middle East, all the way to India. In museums now, you can see Greek coins that have clear images of the Asiatic lion on them. Most of them are dated at around 500 B.C. However, Europe saw its last Asiatic lions roaming free two thousand years ago. Over the next nineteen hundred years the numbers of Asiatic lions in the other areas declined steadily, but it was only in the nineteenth century that they disappeared from everywhere but in India.

The Gir Wildlife Sanctuary in India was established especially to protect the Asiatic lion. There are now around three hundred Asiatic lions in India and almost all of them are in this sanctuary. However, despite living in a sanctuary, which makes them safe from hunters, they still face a number of problems that threaten their survival. One of these is the ever-present danger of disease. This is what killed more than a third of Africa’s Serengeti lions in 1994, and people are fearful that something similar could happen in the Gir Sanctuary and kill off many of the Asiatic lions there.

India's lions are particular vulnerable because they have a limited gene pool. The reason for this is interesting is because all of them are descended from a few dozen lions that were saved by a prince who took a particular interest in them. He was very healthy, and he managed to protect them; otherwise they would probably have died out completely. When you see the Asiatic lion in India, what you sense is enormous vitality. They are very impressive animals and you would never guess that they have this vulnerability when you look at them.

A. lions roamed much more than nowadays

B. lions did not live in small forests

C. lions came mainly from Africa

D. there were much more lion habitats than nowadays

Most people think that lions only come from Africa. This is understandable because in fact most lions do come from there but this has not always been the case. If we went back ten thousand years, we would find that there were lions roaming vast sections of the globe. However now, unfortunately only a very small section of the lion's former habitat remains. Asiatic lions are sub-species of African lions. It is almost a hundred thousand years since the Asiatic lions split off and developed as a sub-species. At one time the Asiatic lion was living as far west as Greece and they were found from there, but in a band that spreads east through various countries of the Middle East, all the way to India. In museums now, you can see Greek coins that have clear images of the Asiatic lion on them. Most of them are dated at around 500 B.C. However, Europe saw its last Asiatic lions roaming free two thousand years ago. Over the next nineteen hundred years the numbers of Asiatic lions in the other areas declined steadily, but it was only in the nineteenth century that they disappeared from everywhere but in India.

The Gir Wildlife Sanctuary in India was established especially to protect the Asiatic lion. There are now around three hundred Asiatic lions in India and almost all of them are in this sanctuary. However, despite living in a sanctuary, which makes them safe from hunters, they still face a number of problems that threaten their survival. One of these is the ever-present danger of disease. This is what killed more than a third of Africa’s Serengeti lions in 1994, and people are fearful that something similar could happen in the Gir Sanctuary and kill off many of the Asiatic lions there.

India's lions are particular vulnerable because they have a limited gene pool. The reason for this is interesting is because all of them are descended from a few dozen lions that were saved by a prince who took a particular interest in them. He was very healthy, and he managed to protect them; otherwise they would probably have died out completely. When you see the Asiatic lion in India, what you sense is enormous vitality. They are very impressive animals and you would never guess that they have this vulnerability when you look at them.

A. developed into different species

B. changed the original species

C. spotted animals

D. divided

Most people think that lions only come from Africa. This is understandable because in fact most lions do come from there but this has not always been the case. If we went back ten thousand years, we would find that there were lions roaming vast sections of the globe. However now, unfortunately only a very small section of the lion's former habitat remains. Asiatic lions are sub-species of African lions. It is almost a hundred thousand years since the Asiatic lions split off and developed as a sub-species. At one time the Asiatic lion was living as far west as Greece and they were found from there, but in a band that spreads east through various countries of the Middle East, all the way to India. In museums now, you can see Greek coins that have clear images of the Asiatic lion on them. Most of them are dated at around 500 B.C. However, Europe saw its last Asiatic lions roaming free two thousand years ago. Over the next nineteen hundred years the numbers of Asiatic lions in the other areas declined steadily, but it was only in the nineteenth century that they disappeared from everywhere but in India.

The Gir Wildlife Sanctuary in India was established especially to protect the Asiatic lion. There are now around three hundred Asiatic lions in India and almost all of them are in this sanctuary. However, despite living in a sanctuary, which makes them safe from hunters, they still face a number of problems that threaten their survival. One of these is the ever-present danger of disease. This is what killed more than a third of Africa’s Serengeti lions in 1994, and people are fearful that something similar could happen in the Gir Sanctuary and kill off many of the Asiatic lions there.

India's lions are particular vulnerable because they have a limited gene pool. The reason for this is interesting is because all of them are descended from a few dozen lions that were saved by a prince who took a particular interest in them. He was very healthy, and he managed to protect them; otherwise they would probably have died out completely. When you see the Asiatic lion in India, what you sense is enormous vitality. They are very impressive animals and you would never guess that they have this vulnerability when you look at them.

A. in Africa and India

B. only in India

C. nowhere in the world

D. only in Greek museums

Most people think that lions only come from Africa. This is understandable because in fact most lions do come from there but this has not always been the case. If we went back ten thousand years, we would find that there were lions roaming vast sections of the globe. However now, unfortunately only a very small section of the lion's former habitat remains. Asiatic lions are sub-species of African lions. It is almost a hundred thousand years since the Asiatic lions split off and developed as a sub-species. At one time the Asiatic lion was living as far west as Greece and they were found from there, but in a band that spreads east through various countries of the Middle East, all the way to India. In museums now, you can see Greek coins that have clear images of the Asiatic lion on them. Most of them are dated at around 500 B.C. However, Europe saw its last Asiatic lions roaming free two thousand years ago. Over the next nineteen hundred years the numbers of Asiatic lions in the other areas declined steadily, but it was only in the nineteenth century that they disappeared from everywhere but in India.

The Gir Wildlife Sanctuary in India was established especially to protect the Asiatic lion. There are now around three hundred Asiatic lions in India and almost all of them are in this sanctuary. However, despite living in a sanctuary, which makes them safe from hunters, they still face a number of problems that threaten their survival. One of these is the ever-present danger of disease. This is what killed more than a third of Africa’s Serengeti lions in 1994, and people are fearful that something similar could happen in the Gir Sanctuary and kill off many of the Asiatic lions there.

India's lions are particular vulnerable because they have a limited gene pool. The reason for this is interesting is because all of them are descended from a few dozen lions that were saved by a prince who took a particular interest in them. He was very healthy, and he managed to protect them; otherwise they would probably have died out completely. When you see the Asiatic lion in India, what you sense is enormous vitality. They are very impressive animals and you would never guess that they have this vulnerability when you look at them.

A. easily protected

B. weak

C. careless

D. cautious

Most people think that lions only come from Africa. This is understandable because in fact most lions do come from there but this has not always been the case. If we went back ten thousand years, we would find that there were lions roaming vast sections of the globe. However now, unfortunately only a very small section of the lion's former habitat remains. Asiatic lions are sub-species of African lions. It is almost a hundred thousand years since the Asiatic lions split off and developed as a sub-species. At one time the Asiatic lion was living as far west as Greece and they were found from there, but in a band that spreads east through various countries of the Middle East, all the way to India. In museums now, you can see Greek coins that have clear images of the Asiatic lion on them. Most of them are dated at around 500 B.C. However, Europe saw its last Asiatic lions roaming free two thousand years ago. Over the next nineteen hundred years the numbers of Asiatic lions in the other areas declined steadily, but it was only in the nineteenth century that they disappeared from everywhere but in India.

The Gir Wildlife Sanctuary in India was established especially to protect the Asiatic lion. There are now around three hundred Asiatic lions in India and almost all of them are in this sanctuary. However, despite living in a sanctuary, which makes them safe from hunters, they still face a number of problems that threaten their survival. One of these is the ever-present danger of disease. This is what killed more than a third of Africa’s Serengeti lions in 1994, and people are fearful that something similar could happen in the Gir Sanctuary and kill off many of the Asiatic lions there.

India's lions are particular vulnerable because they have a limited gene pool. The reason for this is interesting is because all of them are descended from a few dozen lions that were saved by a prince who took a particular interest in them. He was very healthy, and he managed to protect them; otherwise they would probably have died out completely. When you see the Asiatic lion in India, what you sense is enormous vitality. They are very impressive animals and you would never guess that they have this vulnerability when you look at them.

A. was searching for food in a wide range of countries

B. was searching for food mainly in India and Africa

C. was looking for food mainly in the Middle East

D. was looking for food mainly in India

Most people think that lions only come from Africa. This is understandable because in fact most lions do come from there but this has not always been the case. If we went back ten thousand years, we would find that there were lions roaming vast sections of the globe. However now, unfortunately only a very small section of the lion's former habitat remains. Asiatic lions are sub-species of African lions. It is almost a hundred thousand years since the Asiatic lions split off and developed as a sub-species. At one time the Asiatic lion was living as far west as Greece and they were found from there, but in a band that spreads east through various countries of the Middle East, all the way to India. In museums now, you can see Greek coins that have clear images of the Asiatic lion on them. Most of them are dated at around 500 B.C. However, Europe saw its last Asiatic lions roaming free two thousand years ago. Over the next nineteen hundred years the numbers of Asiatic lions in the other areas declined steadily, but it was only in the nineteenth century that they disappeared from everywhere but in India.

The Gir Wildlife Sanctuary in India was established especially to protect the Asiatic lion. There are now around three hundred Asiatic lions in India and almost all of them are in this sanctuary. However, despite living in a sanctuary, which makes them safe from hunters, they still face a number of problems that threaten their survival. One of these is the ever-present danger of disease. This is what killed more than a third of Africa’s Serengeti lions in 1994, and people are fearful that something similar could happen in the Gir Sanctuary and kill off many of the Asiatic lions there.

India's lions are particular vulnerable because they have a limited gene pool. The reason for this is interesting is because all of them are descended from a few dozen lions that were saved by a prince who took a particular interest in them. He was very healthy, and he managed to protect them; otherwise they would probably have died out completely. When you see the Asiatic lion in India, what you sense is enormous vitality. They are very impressive animals and you would never guess that they have this vulnerability when you look at them.

A. the Asiatic lion was loved by a wealthy prince

B. the current Asiatic lions come from a great number of lions

C. a rich prince sponsored the protection of Asiatic lions

D. although the Asiatic lion looks strong from appearance they are easily attacked by diseases

Most people think that lions only come from Africa. This is understandable because in fact most lions do come from there but this has not always been the case. If we went back ten thousand years, we would find that there were lions roaming vast sections of the globe. However now, unfortunately only a very small section of the lion's former habitat remains. Asiatic lions are sub-species of African lions. It is almost a hundred thousand years since the Asiatic lions split off and developed as a sub-species. At one time the Asiatic lion was living as far west as Greece and they were found from there, but in a band that spreads east through various countries of the Middle East, all the way to India. In museums now, you can see Greek coins that have clear images of the Asiatic lion on them. Most of them are dated at around 500 B.C. However, Europe saw its last Asiatic lions roaming free two thousand years ago. Over the next nineteen hundred years the numbers of Asiatic lions in the other areas declined steadily, but it was only in the nineteenth century that they disappeared from everywhere but in India.

The Gir Wildlife Sanctuary in India was established especially to protect the Asiatic lion. There are now around three hundred Asiatic lions in India and almost all of them are in this sanctuary. However, despite living in a sanctuary, which makes them safe from hunters, they still face a number of problems that threaten their survival. One of these is the ever-present danger of disease. This is what killed more than a third of Africa’s Serengeti lions in 1994, and people are fearful that something similar could happen in the Gir Sanctuary and kill off many of the Asiatic lions there.

India's lions are particular vulnerable because they have a limited gene pool. The reason for this is interesting is because all of them are descended from a few dozen lions that were saved by a prince who took a particular interest in them. He was very healthy, and he managed to protect them; otherwise they would probably have died out completely. When you see the Asiatic lion in India, what you sense is enormous vitality. They are very impressive animals and you would never guess that they have this vulnerability when you look at them.

A. explain why the Gir Sanctuary is the best habitat for the Asiatic lions

B. provide an overview of the existence of the Asiatic lions

C. describe the developmental history of the Gir Sanctuary

D. persuade readers to protect the Asiatic lions

The Development of Refrigeration

Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses.

Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled.

Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries.

Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines.

The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.

A. They wanted to improve the flavor and nutritional value of food.

B. They needed to slow the natural processes that cause food to spoil.

C. They needed to use for the ice that formed on lakes and rivers.

D. They wanted to expand the production of certain industries.

The Development of Refrigeration

Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses.

Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled.

Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries.

Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines.

The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.

A. capable of spoiling

B. uncooked

C. of animal origin

D. highly nutritious

The Development of Refrigeration

Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses.

Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled.

Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries.

Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines.

The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.

A. It kept food cold for only about a week.

B. It was dependent on a source of ice or snow.

C. It required a container made of mental or wood.

D. It was not a safe method of preserving meat.

The Development of Refrigeration

Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses.

Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled.

Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries.

Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines.

The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.

A. the pumping of water vapor through a pipe.

B. the rapid expansion of certain gases.

C. the evaporation of a volatile liquid.

D. the transfer of heat from one place to another.

The Development of Refrigeration

Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses.

Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled.

Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries.

Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines.

The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.

A. William Cullen

B. Oliver Evans

C. John Gorrie

D. Adolphus Busch

The Development of Refrigeration

Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses.

Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled.

Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries.

Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines.

The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.

A. printer

B. refrigerator

C. type

D. ether

The Development of Refrigeration

Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses.

Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled.

Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries.

Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines.

The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.

A. restricted

B. spoiled

C. improved

D. alternated

The Development of Refrigeration

Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses.

Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled.

Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries.

Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines.

The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.

A. ether

B. ice

C. ammonia

D. CFCs

In the history of technology, computers and calculators were innovative developments. They are essentially different from all other machines because they have a memory. This memory stores instructions and information. In a calculator, the instructions are the various functions of arithmetic, which are permanently remembered by the machine and cannot be altered or added to. The information consists of the numbers keyed in.

An electronic pocket calculator can perform almost instant arithmetic. A calculator requires an input unit to feed in numbers, a processing unit to make the calculation, a memory unit, and an output unit to display the result. The calculator is powered by a small battery or by a panel of solar cells. Inside is a microchip that contains the memory and processing units and also controls the input unit, which is the keyboard, and the output unit, which is the display.

The input unit has keys for numbers and operations. Beneath the key is a printed circuit board containing a set of contacts for each key. Pressing a key closes the contacts and sends a signal along a pair of lines in the circuit board to the processing unit, in which the binary code for that key is stored in the memory. The processing unit also sends the code to the display. Each key is connected by a different pair of lines to the processing unit, which repeatedly checks the lines to find out when a pair is linked by a key.

The memory unit stores the arithmetic instructions for the processing unit and holds the temporary results that occur during calculation. Storage cells in the memory unit hold the binary codes for the keys that have been pressed. The number codes, together with the operation code for the plus key,   are    held    in    temporary    cells    until    the    processing    unit    requires them. When the equals key is pressed, it sends a signal to the processing unit. This takes the operation code-for example, addition-and the two numbers being held in the memory unit and performs the operation on the two numbers. A full adder does the addition, and the result goes to the decoder in the calculator's microchip. This code is then sent to the liquid crystal display unit, which shows the result, or output, of the calculation.

A. recent

B. important

C. revolutionary

D. complicated

In the history of technology, computers and calculators were innovative developments. They are essentially different from all other machines because they have a memory. This memory stores instructions and information. In a calculator, the instructions are the various functions of arithmetic, which are permanently remembered by the machine and cannot be altered or added to. The information consists of the numbers keyed in.

An electronic pocket calculator can perform almost instant arithmetic. A calculator requires an input unit to feed in numbers, a processing unit to make the calculation, a memory unit, and an output unit to display the result. The calculator is powered by a small battery or by a panel of solar cells. Inside is a microchip that contains the memory and processing units and also controls the input unit, which is the keyboard, and the output unit, which is the display.

The input unit has keys for numbers and operations. Beneath the key is a printed circuit board containing a set of contacts for each key. Pressing a key closes the contacts and sends a signal along a pair of lines in the circuit board to the processing unit, in which the binary code for that key is stored in the memory. The processing unit also sends the code to the display. Each key is connected by a different pair of lines to the processing unit, which repeatedly checks the lines to find out when a pair is linked by a key.

The memory unit stores the arithmetic instructions for the processing unit and holds the temporary results that occur during calculation. Storage cells in the memory unit hold the binary codes for the keys that have been pressed. The number codes, together with the operation code for the plus key,   are    held    in    temporary    cells    until    the    processing    unit    requires them. When the equals key is pressed, it sends a signal to the processing unit. This takes the operation code-for example, addition-and the two numbers being held in the memory unit and performs the operation on the two numbers. A full adder does the addition, and the result goes to the decoder in the calculator's microchip. This code is then sent to the liquid crystal display unit, which shows the result, or output, of the calculation.

A. They can not store information in a memory.

B. They are less expensive than computers.

C. They have simple memory and processing units.

D. They are older than computers.

In the history of technology, computers and calculators were innovative developments. They are essentially different from all other machines because they have a memory. This memory stores instructions and information. In a calculator, the instructions are the various functions of arithmetic, which are permanently remembered by the machine and cannot be altered or added to. The information consists of the numbers keyed in.

An electronic pocket calculator can perform almost instant arithmetic. A calculator requires an input unit to feed in numbers, a processing unit to make the calculation, a memory unit, and an output unit to display the result. The calculator is powered by a small battery or by a panel of solar cells. Inside is a microchip that contains the memory and processing units and also controls the input unit, which is the keyboard, and the output unit, which is the display.

The input unit has keys for numbers and operations. Beneath the key is a printed circuit board containing a set of contacts for each key. Pressing a key closes the contacts and sends a signal along a pair of lines in the circuit board to the processing unit, in which the binary code for that key is stored in the memory. The processing unit also sends the code to the display. Each key is connected by a different pair of lines to the processing unit, which repeatedly checks the lines to find out when a pair is linked by a key.

The memory unit stores the arithmetic instructions for the processing unit and holds the temporary results that occur during calculation. Storage cells in the memory unit hold the binary codes for the keys that have been pressed. The number codes, together with the operation code for the plus key,   are    held    in    temporary    cells    until    the    processing    unit    requires them. When the equals key is pressed, it sends a signal to the processing unit. This takes the operation code-for example, addition-and the two numbers being held in the memory unit and performs the operation on the two numbers. A full adder does the addition, and the result goes to the decoder in the calculator's microchip. This code is then sent to the liquid crystal display unit, which shows the result, or output, of the calculation.

A. the battery  

B. the solar cells

C. the output unit

D. the microchip

In the history of technology, computers and calculators were innovative developments. They are essentially different from all other machines because they have a memory. This memory stores instructions and information. In a calculator, the instructions are the various functions of arithmetic, which are permanently remembered by the machine and cannot be altered or added to. The information consists of the numbers keyed in.

An electronic pocket calculator can perform almost instant arithmetic. A calculator requires an input unit to feed in numbers, a processing unit to make the calculation, a memory unit, and an output unit to display the result. The calculator is powered by a small battery or by a panel of solar cells. Inside is a microchip that contains the memory and processing units and also controls the input unit, which is the keyboard, and the output unit, which is the display.

The input unit has keys for numbers and operations. Beneath the key is a printed circuit board containing a set of contacts for each key. Pressing a key closes the contacts and sends a signal along a pair of lines in the circuit board to the processing unit, in which the binary code for that key is stored in the memory. The processing unit also sends the code to the display. Each key is connected by a different pair of lines to the processing unit, which repeatedly checks the lines to find out when a pair is linked by a key.

The memory unit stores the arithmetic instructions for the processing unit and holds the temporary results that occur during calculation. Storage cells in the memory unit hold the binary codes for the keys that have been pressed. The number codes, together with the operation code for the plus key,   are    held    in    temporary    cells    until    the    processing    unit    requires them. When the equals key is pressed, it sends a signal to the processing unit. This takes the operation code-for example, addition-and the two numbers being held in the memory unit and performs the operation on the two numbers. A full adder does the addition, and the result goes to the decoder in the calculator's microchip. This code is then sent to the liquid crystal display unit, which shows the result, or output, of the calculation.

A. to control the keyboard

B. to store temporary results during calculation

C. to send codes to the display unit

D. to alter basic arithmetic instructions

In the history of technology, computers and calculators were innovative developments. They are essentially different from all other machines because they have a memory. This memory stores instructions and information. In a calculator, the instructions are the various functions of arithmetic, which are permanently remembered by the machine and cannot be altered or added to. The information consists of the numbers keyed in.

An electronic pocket calculator can perform almost instant arithmetic. A calculator requires an input unit to feed in numbers, a processing unit to make the calculation, a memory unit, and an output unit to display the result. The calculator is powered by a small battery or by a panel of solar cells. Inside is a microchip that contains the memory and processing units and also controls the input unit, which is the keyboard, and the output unit, which is the display.

The input unit has keys for numbers and operations. Beneath the key is a printed circuit board containing a set of contacts for each key. Pressing a key closes the contacts and sends a signal along a pair of lines in the circuit board to the processing unit, in which the binary code for that key is stored in the memory. The processing unit also sends the code to the display. Each key is connected by a different pair of lines to the processing unit, which repeatedly checks the lines to find out when a pair is linked by a key.

The memory unit stores the arithmetic instructions for the processing unit and holds the temporary results that occur during calculation. Storage cells in the memory unit hold the binary codes for the keys that have been pressed. The number codes, together with the operation code for the plus key,   are    held    in    temporary    cells    until    the    processing    unit    requires them. When the equals key is pressed, it sends a signal to the processing unit. This takes the operation code-for example, addition-and the two numbers being held in the memory unit and performs the operation on the two numbers. A full adder does the addition, and the result goes to the decoder in the calculator's microchip. This code is then sent to the liquid crystal display unit, which shows the result, or output, of the calculation.

A. the plus key

B. the processing unit

C. the memory unit

D. the equals key

In the history of technology, computers and calculators were innovative developments. They are essentially different from all other machines because they have a memory. This memory stores instructions and information. In a calculator, the instructions are the various functions of arithmetic, which are permanently remembered by the machine and cannot be altered or added to. The information consists of the numbers keyed in.

An electronic pocket calculator can perform almost instant arithmetic. A calculator requires an input unit to feed in numbers, a processing unit to make the calculation, a memory unit, and an output unit to display the result. The calculator is powered by a small battery or by a panel of solar cells. Inside is a microchip that contains the memory and processing units and also controls the input unit, which is the keyboard, and the output unit, which is the display.

The input unit has keys for numbers and operations. Beneath the key is a printed circuit board containing a set of contacts for each key. Pressing a key closes the contacts and sends a signal along a pair of lines in the circuit board to the processing unit, in which the binary code for that key is stored in the memory. The processing unit also sends the code to the display. Each key is connected by a different pair of lines to the processing unit, which repeatedly checks the lines to find out when a pair is linked by a key.

The memory unit stores the arithmetic instructions for the processing unit and holds the temporary results that occur during calculation. Storage cells in the memory unit hold the binary codes for the keys that have been pressed. The number codes, together with the operation code for the plus key,   are    held    in    temporary    cells    until    the    processing    unit    requires them. When the equals key is pressed, it sends a signal to the processing unit. This takes the operation code-for example, addition-and the two numbers being held in the memory unit and performs the operation on the two numbers. A full adder does the addition, and the result goes to the decoder in the calculator's microchip. This code is then sent to the liquid crystal display unit, which shows the result, or output, of the calculation.

A. commands

B. codes

C. locations

D. connections

In the history of technology, computers and calculators were innovative developments. They are essentially different from all other machines because they have a memory. This memory stores instructions and information. In a calculator, the instructions are the various functions of arithmetic, which are permanently remembered by the machine and cannot be altered or added to. The information consists of the numbers keyed in.

An electronic pocket calculator can perform almost instant arithmetic. A calculator requires an input unit to feed in numbers, a processing unit to make the calculation, a memory unit, and an output unit to display the result. The calculator is powered by a small battery or by a panel of solar cells. Inside is a microchip that contains the memory and processing units and also controls the input unit, which is the keyboard, and the output unit, which is the display.

The input unit has keys for numbers and operations. Beneath the key is a printed circuit board containing a set of contacts for each key. Pressing a key closes the contacts and sends a signal along a pair of lines in the circuit board to the processing unit, in which the binary code for that key is stored in the memory. The processing unit also sends the code to the display. Each key is connected by a different pair of lines to the processing unit, which repeatedly checks the lines to find out when a pair is linked by a key.

The memory unit stores the arithmetic instructions for the processing unit and holds the temporary results that occur during calculation. Storage cells in the memory unit hold the binary codes for the keys that have been pressed. The number codes, together with the operation code for the plus key,   are    held    in    temporary    cells    until    the    processing    unit    requires them. When the equals key is pressed, it sends a signal to the processing unit. This takes the operation code-for example, addition-and the two numbers being held in the memory unit and performs the operation on the two numbers. A full adder does the addition, and the result goes to the decoder in the calculator's microchip. This code is then sent to the liquid crystal display unit, which shows the result, or output, of the calculation.

A. The calculator's "thinking" takes place in the processing and memory units.

B. Calculators require a lot of instructions to operate quickly.

C. Calculators and computers are similar.

D. Pressing a key activates a calculator.

In the history of technology, computers and calculators were innovative developments. They are essentially different from all other machines because they have a memory. This memory stores instructions and information. In a calculator, the instructions are the various functions of arithmetic, which are permanently remembered by the machine and cannot be altered or added to. The information consists of the numbers keyed in.

An electronic pocket calculator can perform almost instant arithmetic. A calculator requires an input unit to feed in numbers, a processing unit to make the calculation, a memory unit, and an output unit to display the result. The calculator is powered by a small battery or by a panel of solar cells. Inside is a microchip that contains the memory and processing units and also controls the input unit, which is the keyboard, and the output unit, which is the display.

The input unit has keys for numbers and operations. Beneath the key is a printed circuit board containing a set of contacts for each key. Pressing a key closes the contacts and sends a signal along a pair of lines in the circuit board to the processing unit, in which the binary code for that key is stored in the memory. The processing unit also sends the code to the display. Each key is connected by a different pair of lines to the processing unit, which repeatedly checks the lines to find out when a pair is linked by a key.

The memory unit stores the arithmetic instructions for the processing unit and holds the temporary results that occur during calculation. Storage cells in the memory unit hold the binary codes for the keys that have been pressed. The number codes, together with the operation code for the plus key,   are    held    in    temporary    cells    until    the    processing    unit    requires them. When the equals key is pressed, it sends a signal to the processing unit. This takes the operation code-for example, addition-and the two numbers being held in the memory unit and performs the operation on the two numbers. A full adder does the addition, and the result goes to the decoder in the calculator's microchip. This code is then sent to the liquid crystal display unit, which shows the result, or output, of the calculation.

A. To discuss innovative developments in technology

B. To compare computers and calculators with other machines

C. To summarize the history of technology

D. To explain how a calculator works

   Dodder is an unusual and unwanted plant that attacks other plants. Except for its flowers, the plant looks like spaghetti noodles. Its almost leafless, thread–like stems hang down atop other plants that dodder needs to stay alive. Dodder does not produce its own food. Instead, it steals it from other plants. It feeds by sucking juices from the plant it is wrapped around, often making its host very weak or even killing it. Dodder can find other plants by their smell. When a dodder seedling starts growing, it follows the scent of plants it prefers, like tomato plants, potato plants, or other farm crops.

   Unlike most plants that usually grow in the direction of light or warmth, a dodder plant will grow in the direction of, for example, tomato odor––if a tomato happens to be growing nearby.

   However, a young dodder plant must find a host plant quickly. If it cannot catch a whiff of a potential host within a few days, it will dry up and disappear—even if there is plenty of water around. Once it finds a host, the young dodder plant will attach itself to it and start growing faster. At that point, the dodder plant will drop its root.

   Dodder is thus a difficult weed to manage and a real headache for farmers. When it does get out of hand, dodder can greatly reduce a farmer’s harvest or even destroy crops completely. Before sowing their produce, farmers in warm parts of the world often check to make sure no unwanted dodder seeds have intermingled with their crop seeds. This is a good way to stop dodder plants from sneaking their way into a crop field.

A. A new variety of farm crop

B. Plants that are harmful to humans

C. The special abilities of a dangerous plant

D. Recent improvements in farming methods

   Dodder is an unusual and unwanted plant that attacks other plants. Except for its flowers, the plant looks like spaghetti noodles. Its almost leafless, thread–like stems hang down atop other plants that dodder needs to stay alive. Dodder does not produce its own food. Instead, it steals it from other plants. It feeds by sucking juices from the plant it is wrapped around, often making its host very weak or even killing it. Dodder can find other plants by their smell. When a dodder seedling starts growing, it follows the scent of plants it prefers, like tomato plants, potato plants, or other farm crops.

   Unlike most plants that usually grow in the direction of light or warmth, a dodder plant will grow in the direction of, for example, tomato odor––if a tomato happens to be growing nearby.

   However, a young dodder plant must find a host plant quickly. If it cannot catch a whiff of a potential host within a few days, it will dry up and disappear—even if there is plenty of water around. Once it finds a host, the young dodder plant will attach itself to it and start growing faster. At that point, the dodder plant will drop its root.

   Dodder is thus a difficult weed to manage and a real headache for farmers. When it does get out of hand, dodder can greatly reduce a farmer’s harvest or even destroy crops completely. Before sowing their produce, farmers in warm parts of the world often check to make sure no unwanted dodder seeds have intermingled with their crop seeds. This is a good way to stop dodder plants from sneaking their way into a crop field.

A. To analyze the content of some food

B. To describe the shape of a dodder plant

C. To explain where the dodder plant came from

D. To argue that dodder plants can be used to make food

   Dodder is an unusual and unwanted plant that attacks other plants. Except for its flowers, the plant looks like spaghetti noodles. Its almost leafless, thread–like stems hang down atop other plants that dodder needs to stay alive. Dodder does not produce its own food. Instead, it steals it from other plants. It feeds by sucking juices from the plant it is wrapped around, often making its host very weak or even killing it. Dodder can find other plants by their smell. When a dodder seedling starts growing, it follows the scent of plants it prefers, like tomato plants, potato plants, or other farm crops.

   Unlike most plants that usually grow in the direction of light or warmth, a dodder plant will grow in the direction of, for example, tomato odor––if a tomato happens to be growing nearby.

   However, a young dodder plant must find a host plant quickly. If it cannot catch a whiff of a potential host within a few days, it will dry up and disappear—even if there is plenty of water around. Once it finds a host, the young dodder plant will attach itself to it and start growing faster. At that point, the dodder plant will drop its root.

   Dodder is thus a difficult weed to manage and a real headache for farmers. When it does get out of hand, dodder can greatly reduce a farmer’s harvest or even destroy crops completely. Before sowing their produce, farmers in warm parts of the world often check to make sure no unwanted dodder seeds have intermingled with their crop seeds. This is a good way to stop dodder plants from sneaking their way into a crop field.

A. host

B. food

C. plant

D. dodder

   Dodder is an unusual and unwanted plant that attacks other plants. Except for its flowers, the plant looks like spaghetti noodles. Its almost leafless, thread–like stems hang down atop other plants that dodder needs to stay alive. Dodder does not produce its own food. Instead, it steals it from other plants. It feeds by sucking juices from the plant it is wrapped around, often making its host very weak or even killing it. Dodder can find other plants by their smell. When a dodder seedling starts growing, it follows the scent of plants it prefers, like tomato plants, potato plants, or other farm crops.

   Unlike most plants that usually grow in the direction of light or warmth, a dodder plant will grow in the direction of, for example, tomato odor––if a tomato happens to be growing nearby.

   However, a young dodder plant must find a host plant quickly. If it cannot catch a whiff of a potential host within a few days, it will dry up and disappear—even if there is plenty of water around. Once it finds a host, the young dodder plant will attach itself to it and start growing faster. At that point, the dodder plant will drop its root.

   Dodder is thus a difficult weed to manage and a real headache for farmers. When it does get out of hand, dodder can greatly reduce a farmer’s harvest or even destroy crops completely. Before sowing their produce, farmers in warm parts of the world often check to make sure no unwanted dodder seeds have intermingled with their crop seeds. This is a good way to stop dodder plants from sneaking their way into a crop field.

A. Odor

B. Light

C. Water

D. Temperature

   Dodder is an unusual and unwanted plant that attacks other plants. Except for its flowers, the plant looks like spaghetti noodles. Its almost leafless, thread–like stems hang down atop other plants that dodder needs to stay alive. Dodder does not produce its own food. Instead, it steals it from other plants. It feeds by sucking juices from the plant it is wrapped around, often making its host very weak or even killing it. Dodder can find other plants by their smell. When a dodder seedling starts growing, it follows the scent of plants it prefers, like tomato plants, potato plants, or other farm crops.

   Unlike most plants that usually grow in the direction of light or warmth, a dodder plant will grow in the direction of, for example, tomato odor––if a tomato happens to be growing nearby.

   However, a young dodder plant must find a host plant quickly. If it cannot catch a whiff of a potential host within a few days, it will dry up and disappear—even if there is plenty of water around. Once it finds a host, the young dodder plant will attach itself to it and start growing faster. At that point, the dodder plant will drop its root.

   Dodder is thus a difficult weed to manage and a real headache for farmers. When it does get out of hand, dodder can greatly reduce a farmer’s harvest or even destroy crops completely. Before sowing their produce, farmers in warm parts of the world often check to make sure no unwanted dodder seeds have intermingled with their crop seeds. This is a good way to stop dodder plants from sneaking their way into a crop field.

A. eat the seeds

B. notice the smell

C. find the location

D. determine the size

   Dodder is an unusual and unwanted plant that attacks other plants. Except for its flowers, the plant looks like spaghetti noodles. Its almost leafless, thread–like stems hang down atop other plants that dodder needs to stay alive. Dodder does not produce its own food. Instead, it steals it from other plants. It feeds by sucking juices from the plant it is wrapped around, often making its host very weak or even killing it. Dodder can find other plants by their smell. When a dodder seedling starts growing, it follows the scent of plants it prefers, like tomato plants, potato plants, or other farm crops.

   Unlike most plants that usually grow in the direction of light or warmth, a dodder plant will grow in the direction of, for example, tomato odor––if a tomato happens to be growing nearby.

   However, a young dodder plant must find a host plant quickly. If it cannot catch a whiff of a potential host within a few days, it will dry up and disappear—even if there is plenty of water around. Once it finds a host, the young dodder plant will attach itself to it and start growing faster. At that point, the dodder plant will drop its root.

   Dodder is thus a difficult weed to manage and a real headache for farmers. When it does get out of hand, dodder can greatly reduce a farmer’s harvest or even destroy crops completely. Before sowing their produce, farmers in warm parts of the world often check to make sure no unwanted dodder seeds have intermingled with their crop seeds. This is a good way to stop dodder plants from sneaking their way into a crop field.

A. It will soon die.

B. It will grow deeper roots.

C. It will attract other plants.

D. It will cover the entire area of soil.

   Dodder is an unusual and unwanted plant that attacks other plants. Except for its flowers, the plant looks like spaghetti noodles. Its almost leafless, thread–like stems hang down atop other plants that dodder needs to stay alive. Dodder does not produce its own food. Instead, it steals it from other plants. It feeds by sucking juices from the plant it is wrapped around, often making its host very weak or even killing it. Dodder can find other plants by their smell. When a dodder seedling starts growing, it follows the scent of plants it prefers, like tomato plants, potato plants, or other farm crops.

   Unlike most plants that usually grow in the direction of light or warmth, a dodder plant will grow in the direction of, for example, tomato odor––if a tomato happens to be growing nearby.

   However, a young dodder plant must find a host plant quickly. If it cannot catch a whiff of a potential host within a few days, it will dry up and disappear—even if there is plenty of water around. Once it finds a host, the young dodder plant will attach itself to it and start growing faster. At that point, the dodder plant will drop its root.

   Dodder is thus a difficult weed to manage and a real headache for farmers. When it does get out of hand, dodder can greatly reduce a farmer’s harvest or even destroy crops completely. Before sowing their produce, farmers in warm parts of the world often check to make sure no unwanted dodder seeds have intermingled with their crop seeds. This is a good way to stop dodder plants from sneaking their way into a crop field.

A. dry up and die

B. change its color

C. become hard to find

D. grow uncontrollably

   We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

   Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

   In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers. Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal.

A. recommend pair work and group work classroom activities

B. emphasize the importance of appropriate formal classroom teaching

C. offer advice on the proper use of the school library

D. argue for teaching bright and not-so-bright pupils in the same class

   We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

   Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

   In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers. Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal.

A. Pupils as individuals always have the opportunities to work on their own.

B. Pupils can be hindered from an all-round development.

C. Formal class teaching is the important way to give the pupils essential skills such as those to be used in the library.

D. A pupil can be at the bottom of a class.

   We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

   Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

   In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers. Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal.

A. forced to study in lower classes

B. prevented from advancing

C. made to lag behind

D. made to remain in the same classes

   We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

   Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

   In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers. Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal.

A. Various ways of teaching should be encouraged in class.

B. The aim of education is to find out how to teach the bright and not-so-bright pupils.

C. Bright children do benefit from mixed-class teaching.

D. Children, in general, develop at different rates.

   We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

   Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

   In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers. Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal.

A. will help the pupils learn best

B. is quite discouraging

C. is the act of putting pupils into classes according to their academic abilities

D. aims at enriching both their knowledge and experience

   We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

   Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

   In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers. Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal.

A. questioning

B. objective

C. ritical

D. approving

   We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

   Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

   In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers. Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal.

A. Pupils cannot develop in the best way if they are streamed into classes of different intellectual abilities.

B. There is no fixed method in teaching pupils to develop themselves to the full.

C. It’s not good for a bright child to find out that he performs worst in a mixed-ability class.

D. Development of pupils as individuals is not the aim of group work.

   Telecommuting is a form of computer communication between employees’ homes and offices. For employees whose jobs involve sitting at a terminal or word processor entering data or typing reports, the location of the computer is of no consequence. If the machine can communicate over telephone lines, when the work is completed, employees can dial the office computer and transmit the material to their employers. A recent survey in USA Today estimates that there are approximately 8,7 million telecommuters. But although the numbers are rising annually, the trend does not appear to be as significant as predicted when Business Week published “The Portable

   Executive” as its cover story a few years ago. Why hasn’t telecommuting become more popular ?

   Clearly, change simply takes time. But in addition, there has been active resistance on the part of many managers. These executives claim that supervising the telecommuters in a large work force scattered across the country would be too difficult, or, at least, systems for managing them are not yet developed, thereby complicating the manager’s responsibilities.

   It is also true that employees who are given the option of telecommuting are reluctant to accept the opportunity. Most people feel that they need regular interaction with a group, and many are concerned that they will not have the same consideration for advancement if they are not more visible in the office setting. Some people feel that even when a space in their homes is set aside as a work area, they never really get away from the office.

A. More than predicted in Business Week.

B. More than 8 million.

C. Fewer than estimated in USA Today.

D. Fewer than last year.

   Telecommuting is a form of computer communication between employees’ homes and offices. For employees whose jobs involve sitting at a terminal or word processor entering data or typing reports, the location of the computer is of no consequence. If the machine can communicate over telephone lines, when the work is completed, employees can dial the office computer and transmit the material to their employers. A recent survey in USA Today estimates that there are approximately 8,7 million telecommuters. But although the numbers are rising annually, the trend does not appear to be as significant as predicted when Business Week published “The Portable

   Executive” as its cover story a few years ago. Why hasn’t telecommuting become more popular ?

   Clearly, change simply takes time. But in addition, there has been active resistance on the part of many managers. These executives claim that supervising the telecommuters in a large work force scattered across the country would be too difficult, or, at least, systems for managing them are not yet developed, thereby complicating the manager’s responsibilities.

   It is also true that employees who are given the option of telecommuting are reluctant to accept the opportunity. Most people feel that they need regular interaction with a group, and many are concerned that they will not have the same consideration for advancement if they are not more visible in the office setting. Some people feel that even when a space in their homes is set aside as a work area, they never really get away from the office.

A. of no use

B. of no good

C. unimportant

D. irrelevant

   Telecommuting is a form of computer communication between employees’ homes and offices. For employees whose jobs involve sitting at a terminal or word processor entering data or typing reports, the location of the computer is of no consequence. If the machine can communicate over telephone lines, when the work is completed, employees can dial the office computer and transmit the material to their employers. A recent survey in USA Today estimates that there are approximately 8,7 million telecommuters. But although the numbers are rising annually, the trend does not appear to be as significant as predicted when Business Week published “The Portable

   Executive” as its cover story a few years ago. Why hasn’t telecommuting become more popular ?

   Clearly, change simply takes time. But in addition, there has been active resistance on the part of many managers. These executives claim that supervising the telecommuters in a large work force scattered across the country would be too difficult, or, at least, systems for managing them are not yet developed, thereby complicating the manager’s responsibilities.

   It is also true that employees who are given the option of telecommuting are reluctant to accept the opportunity. Most people feel that they need regular interaction with a group, and many are concerned that they will not have the same consideration for advancement if they are not more visible in the office setting. Some people feel that even when a space in their homes is set aside as a work area, they never really get away from the office.

A. the opportunities for advancement

B. the different system of supervision

C. the lack of interaction with a group

D. The work place is in the home

   Telecommuting is a form of computer communication between employees’ homes and offices. For employees whose jobs involve sitting at a terminal or word processor entering data or typing reports, the location of the computer is of no consequence. If the machine can communicate over telephone lines, when the work is completed, employees can dial the office computer and transmit the material to their employers. A recent survey in USA Today estimates that there are approximately 8,7 million telecommuters. But although the numbers are rising annually, the trend does not appear to be as significant as predicted when Business Week published “The Portable

   Executive” as its cover story a few years ago. Why hasn’t telecommuting become more popular ?

   Clearly, change simply takes time. But in addition, there has been active resistance on the part of many managers. These executives claim that supervising the telecommuters in a large work force scattered across the country would be too difficult, or, at least, systems for managing them are not yet developed, thereby complicating the manager’s responsibilities.

   It is also true that employees who are given the option of telecommuting are reluctant to accept the opportunity. Most people feel that they need regular interaction with a group, and many are concerned that they will not have the same consideration for advancement if they are not more visible in the office setting. Some people feel that even when a space in their homes is set aside as a work area, they never really get away from the office.

A. systems

B. telecommuters

C. executives

D. responsibilities

   Telecommuting is a form of computer communication between employees’ homes and offices. For employees whose jobs involve sitting at a terminal or word processor entering data or typing reports, the location of the computer is of no consequence. If the machine can communicate over telephone lines, when the work is completed, employees can dial the office computer and transmit the material to their employers. A recent survey in USA Today estimates that there are approximately 8,7 million telecommuters. But although the numbers are rising annually, the trend does not appear to be as significant as predicted when Business Week published “The Portable

   Executive” as its cover story a few years ago. Why hasn’t telecommuting become more popular ?

   Clearly, change simply takes time. But in addition, there has been active resistance on the part of many managers. These executives claim that supervising the telecommuters in a large work force scattered across the country would be too difficult, or, at least, systems for managing them are not yet developed, thereby complicating the manager’s responsibilities.

   It is also true that employees who are given the option of telecommuting are reluctant to accept the opportunity. Most people feel that they need regular interaction with a group, and many are concerned that they will not have the same consideration for advancement if they are not more visible in the office setting. Some people feel that even when a space in their homes is set aside as a work area, they never really get away from the office.

A. needn't regular interaction with their families

B. are worried about the promotion if they are not seen at the office

C. like that a work area in their home is away from the office

D. are ignorant of telecommuting

   Telecommuting is a form of computer communication between employees’ homes and offices. For employees whose jobs involve sitting at a terminal or word processor entering data or typing reports, the location of the computer is of no consequence. If the machine can communicate over telephone lines, when the work is completed, employees can dial the office computer and transmit the material to their employers. A recent survey in USA Today estimates that there are approximately 8,7 million telecommuters. But although the numbers are rising annually, the trend does not appear to be as significant as predicted when Business Week published “The Portable

   Executive” as its cover story a few years ago. Why hasn’t telecommuting become more popular ?

   Clearly, change simply takes time. But in addition, there has been active resistance on the part of many managers. These executives claim that supervising the telecommuters in a large work force scattered across the country would be too difficult, or, at least, systems for managing them are not yet developed, thereby complicating the manager’s responsibilities.

   It is also true that employees who are given the option of telecommuting are reluctant to accept the opportunity. Most people feel that they need regular interaction with a group, and many are concerned that they will not have the same consideration for advancement if they are not more visible in the office setting. Some people feel that even when a space in their homes is set aside as a work area, they never really get away from the office.

A. a telecommuter

B. the manager

C. a statistician

D. a reporter

   Telecommuting is a form of computer communication between employees’ homes and offices. For employees whose jobs involve sitting at a terminal or word processor entering data or typing reports, the location of the computer is of no consequence. If the machine can communicate over telephone lines, when the work is completed, employees can dial the office computer and transmit the material to their employers. A recent survey in USA Today estimates that there are approximately 8,7 million telecommuters. But although the numbers are rising annually, the trend does not appear to be as significant as predicted when Business Week published “The Portable

   Executive” as its cover story a few years ago. Why hasn’t telecommuting become more popular ?

   Clearly, change simply takes time. But in addition, there has been active resistance on the part of many managers. These executives claim that supervising the telecommuters in a large work force scattered across the country would be too difficult, or, at least, systems for managing them are not yet developed, thereby complicating the manager’s responsibilities.

   It is also true that employees who are given the option of telecommuting are reluctant to accept the opportunity. Most people feel that they need regular interaction with a group, and many are concerned that they will not have the same consideration for advancement if they are not more visible in the office setting. Some people feel that even when a space in their homes is set aside as a work area, they never really get away from the office.

A. systems for managing telecommuters were not effective

B. there was resistance on the part of many managers about telecommuting

C. the trend for telecommuting was optimistic

D. most telecommuters were satisfied with their work

In the 1960s, The Beatles were probably the most famous pop group in the whole world. Since then, there havebeen a great many groups that have achieved enormous fame, so it is perhaps difficult now to imagine how sensational The Beatles were at that time. They were four boys from the north of England and none of them had any training in music. They started by performing and recording songs by black Americans and they had some success with these songs. Then they started writing their own songs and that was when they became really popular. The Beatles changed pop music. They were the first pop group to achieve great success from songs they had written themselves. After that it became common for groups and singers to write their own songs. The Beatles did not have a long career. Their first hit record was in 1963 and they split up in 1970. They stopped doing live performances in 1966 because it had become too dangerous for them - their fans were so excited that they surrounded them and tried to take their clothes as souvenirs! However, today some of their songs remain as famous as they were when they first came out. Throughout the world, many people can sing part of a Beatles song if you ask them.

A. why the Beatles split up after 7 years

B. the Beatles' fame and success

C. many people's ability to sing a Beatles song

D. how the Beatles became more successful than other groups

In the 1960s, The Beatles were probably the most famous pop group in the whole world. Since then, there havebeen a great many groups that have achieved enormous fame, so it is perhaps difficult now to imagine how sensational The Beatles were at that time. They were four boys from the north of England and none of them had any training in music. They started by performing and recording songs by black Americans and they had some success with these songs. Then they started writing their own songs and that was when they became really popular. The Beatles changed pop music. They were the first pop group to achieve great success from songs they had written themselves. After that it became common for groups and singers to write their own songs. The Beatles did not have a long career. Their first hit record was in 1963 and they split up in 1970. They stopped doing live performances in 1966 because it had become too dangerous for them - their fans were so excited that they surrounded them and tried to take their clothes as souvenirs! However, today some of their songs remain as famous as they were when they first came out. Throughout the world, many people can sing part of a Beatles song if you ask them.

A. came from the same family

B. were at the same age

C. came from a town in the north of England

D. received good training in music

In the 1960s, The Beatles were probably the most famous pop group in the whole world. Since then, there havebeen a great many groups that have achieved enormous fame, so it is perhaps difficult now to imagine how sensational The Beatles were at that time. They were four boys from the north of England and none of them had any training in music. They started by performing and recording songs by black Americans and they had some success with these songs. Then they started writing their own songs and that was when they became really popular. The Beatles changed pop music. They were the first pop group to achieve great success from songs they had written themselves. After that it became common for groups and singers to write their own songs. The Beatles did not have a long career. Their first hit record was in 1963 and they split up in 1970. They stopped doing live performances in 1966 because it had become too dangerous for them - their fans were so excited that they surrounded them and tried to take their clothes as souvenirs! However, today some of their songs remain as famous as they were when they first came out. Throughout the world, many people can sing part of a Beatles song if you ask them.

A. notorious

B. shocking

C. bad

D. popular

In the 1960s, The Beatles were probably the most famous pop group in the whole world. Since then, there havebeen a great many groups that have achieved enormous fame, so it is perhaps difficult now to imagine how sensational The Beatles were at that time. They were four boys from the north of England and none of them had any training in music. They started by performing and recording songs by black Americans and they had some success with these songs. Then they started writing their own songs and that was when they became really popular. The Beatles changed pop music. They were the first pop group to achieve great success from songs they had written themselves. After that it became common for groups and singers to write their own songs. The Beatles did not have a long career. Their first hit record was in 1963 and they split up in 1970. They stopped doing live performances in 1966 because it had become too dangerous for them - their fans were so excited that they surrounded them and tried to take their clothes as souvenirs! However, today some of their songs remain as famous as they were when they first came out. Throughout the world, many people can sing part of a Beatles song if you ask them.

A. written by black American

B. broadcast on the radio

C. paid a lot of money

D. written by themselves

In the 1960s, The Beatles were probably the most famous pop group in the whole world. Since then, there havebeen a great many groups that have achieved enormous fame, so it is perhaps difficult now to imagine how sensational The Beatles were at that time. They were four boys from the north of England and none of them had any training in music. They started by performing and recording songs by black Americans and they had some success with these songs. Then they started writing their own songs and that was when they became really popular. The Beatles changed pop music. They were the first pop group to achieve great success from songs they had written themselves. After that it became common for groups and singers to write their own songs. The Beatles did not have a long career. Their first hit record was in 1963 and they split up in 1970. They stopped doing live performances in 1966 because it had become too dangerous for them - their fans were so excited that they surrounded them and tried to take their clothes as souvenirs! However, today some of their songs remain as famous as they were when they first came out. Throughout the world, many people can sing part of a Beatles song if you ask them.

A. The members had no training in music.

B. They became famous when they wrote their own songs.

C. They had a long stable career.

D. They were afraid of being hurt by fans.

In the 1960s, The Beatles were probably the most famous pop group in the whole world. Since then, there havebeen a great many groups that have achieved enormous fame, so it is perhaps difficult now to imagine how sensational The Beatles were at that time. They were four boys from the north of England and none of them had any training in music. They started by performing and recording songs by black Americans and they had some success with these songs. Then they started writing their own songs and that was when they became really popular. The Beatles changed pop music. They were the first pop group to achieve great success from songs they had written themselves. After that it became common for groups and singers to write their own songs. The Beatles did not have a long career. Their first hit record was in 1963 and they split up in 1970. They stopped doing live performances in 1966 because it had become too dangerous for them - their fans were so excited that they surrounded them and tried to take their clothes as souvenirs! However, today some of their songs remain as famous as they were when they first came out. Throughout the world, many people can sing part of a Beatles song if you ask them.

A. they had earned enough money

B. they did not want to work with each other

C. they spent more time writing their own songs

D. they were afraid of being hurt by fan

In the 1960s, The Beatles were probably the most famous pop group in the whole world. Since then, there havebeen a great many groups that have achieved enormous fame, so it is perhaps difficult now to imagine how sensational The Beatles were at that time. They were four boys from the north of England and none of them had any training in music. They started by performing and recording songs by black Americans and they had some success with these songs. Then they started writing their own songs and that was when they became really popular. The Beatles changed pop music. They were the first pop group to achieve great success from songs they had written themselves. After that it became common for groups and singers to write their own songs. The Beatles did not have a long career. Their first hit record was in 1963 and they split up in 1970. They stopped doing live performances in 1966 because it had become too dangerous for them - their fans were so excited that they surrounded them and tried to take their clothes as souvenirs! However, today some of their songs remain as famous as they were when they first came out. Throughout the world, many people can sing part of a Beatles song if you ask them.

A. the first

B. the singers

C. the songs

D. the performances

   Orchids are unique in having the most highly developed of all blossoms, in which the usual male and female reproductive organs are fused in a single structure called the column. The column is designed so that a single pollination will fertilize hundreds of thousands, and in some cases millions, of seeds, so microscopic and light they are easily carried by the breeze. Surrounding the column are three sepals and three petals, sometimes easily recognizable as such, often distorted into gorgeous, weird, but always functional shapes. The most noticeable of the petals is called the labellum, or lip. It is often dramatically marked as an unmistakable landing strip to attract the specific insect the orchid has chosen as its pollinator. To lure their pollinators from afar, orchids use appropriately intriguing shapes, colors, and scents. At least 50 different aromatic compounds have been analyzed in the orchid family, each blended to attract one, or at most a few, species of insects or birds. Some orchids even change their scents to interest different insects at different times.

   Once the right insect has been attracted, some orchids present all sorts of one-way obstacle courses to make sure it does not leave until pollen has been accurately placed or removed. By such ingenious adaptations to specific pollinators, orchids have avoided the hazards of rampant crossbreeding in the wild, assuring the survival of species as discrete identities. At the same time they have made themselves irresistible to collectors.

A. Birds

B. Insects

C. Flowers

D. Perfume

   Orchids are unique in having the most highly developed of all blossoms, in which the usual male and female reproductive organs are fused in a single structure called the column. The column is designed so that a single pollination will fertilize hundreds of thousands, and in some cases millions, of seeds, so microscopic and light they are easily carried by the breeze. Surrounding the column are three sepals and three petals, sometimes easily recognizable as such, often distorted into gorgeous, weird, but always functional shapes. The most noticeable of the petals is called the labellum, or lip. It is often dramatically marked as an unmistakable landing strip to attract the specific insect the orchid has chosen as its pollinator. To lure their pollinators from afar, orchids use appropriately intriguing shapes, colors, and scents. At least 50 different aromatic compounds have been analyzed in the orchid family, each blended to attract one, or at most a few, species of insects or birds. Some orchids even change their scents to interest different insects at different times.

   Once the right insect has been attracted, some orchids present all sorts of one-way obstacle courses to make sure it does not leave until pollen has been accurately placed or removed. By such ingenious adaptations to specific pollinators, orchids have avoided the hazards of rampant crossbreeding in the wild, assuring the survival of species as discrete identities. At the same time they have made themselves irresistible to collectors.

A. the habitat in which it lives

B. the structure of its blossom

C. the variety of products that can be made from it

D. the length of its life

   Orchids are unique in having the most highly developed of all blossoms, in which the usual male and female reproductive organs are fused in a single structure called the column. The column is designed so that a single pollination will fertilize hundreds of thousands, and in some cases millions, of seeds, so microscopic and light they are easily carried by the breeze. Surrounding the column are three sepals and three petals, sometimes easily recognizable as such, often distorted into gorgeous, weird, but always functional shapes. The most noticeable of the petals is called the labellum, or lip. It is often dramatically marked as an unmistakable landing strip to attract the specific insect the orchid has chosen as its pollinator. To lure their pollinators from afar, orchids use appropriately intriguing shapes, colors, and scents. At least 50 different aromatic compounds have been analyzed in the orchid family, each blended to attract one, or at most a few, species of insects or birds. Some orchids even change their scents to interest different insects at different times.

   Once the right insect has been attracted, some orchids present all sorts of one-way obstacle courses to make sure it does not leave until pollen has been accurately placed or removed. By such ingenious adaptations to specific pollinators, orchids have avoided the hazards of rampant crossbreeding in the wild, assuring the survival of species as discrete identities. At the same time they have made themselves irresistible to collectors.

A. combined

B. hidden

C. fertilized

D. produced

   Orchids are unique in having the most highly developed of all blossoms, in which the usual male and female reproductive organs are fused in a single structure called the column. The column is designed so that a single pollination will fertilize hundreds of thousands, and in some cases millions, of seeds, so microscopic and light they are easily carried by the breeze. Surrounding the column are three sepals and three petals, sometimes easily recognizable as such, often distorted into gorgeous, weird, but always functional shapes. The most noticeable of the petals is called the labellum, or lip. It is often dramatically marked as an unmistakable landing strip to attract the specific insect the orchid has chosen as its pollinator. To lure their pollinators from afar, orchids use appropriately intriguing shapes, colors, and scents. At least 50 different aromatic compounds have been analyzed in the orchid family, each blended to attract one, or at most a few, species of insects or birds. Some orchids even change their scents to interest different insects at different times.

   Once the right insect has been attracted, some orchids present all sorts of one-way obstacle courses to make sure it does not leave until pollen has been accurately placed or removed. By such ingenious adaptations to specific pollinators, orchids have avoided the hazards of rampant crossbreeding in the wild, assuring the survival of species as discrete identities. At the same time they have made themselves irresistible to collectors.

A. 200

B. 2,000

C. 20,000

D. 200,000

   Orchids are unique in having the most highly developed of all blossoms, in which the usual male and female reproductive organs are fused in a single structure called the column. The column is designed so that a single pollination will fertilize hundreds of thousands, and in some cases millions, of seeds, so microscopic and light they are easily carried by the breeze. Surrounding the column are three sepals and three petals, sometimes easily recognizable as such, often distorted into gorgeous, weird, but always functional shapes. The most noticeable of the petals is called the labellum, or lip. It is often dramatically marked as an unmistakable landing strip to attract the specific insect the orchid has chosen as its pollinator. To lure their pollinators from afar, orchids use appropriately intriguing shapes, colors, and scents. At least 50 different aromatic compounds have been analyzed in the orchid family, each blended to attract one, or at most a few, species of insects or birds. Some orchids even change their scents to interest different insects at different times.

   Once the right insect has been attracted, some orchids present all sorts of one-way obstacle courses to make sure it does not leave until pollen has been accurately placed or removed. By such ingenious adaptations to specific pollinators, orchids have avoided the hazards of rampant crossbreeding in the wild, assuring the survival of species as discrete identities. At the same time they have made themselves irresistible to collectors.

A. The column

B. The sepal

C. The stem

D. The labellum

   Orchids are unique in having the most highly developed of all blossoms, in which the usual male and female reproductive organs are fused in a single structure called the column. The column is designed so that a single pollination will fertilize hundreds of thousands, and in some cases millions, of seeds, so microscopic and light they are easily carried by the breeze. Surrounding the column are three sepals and three petals, sometimes easily recognizable as such, often distorted into gorgeous, weird, but always functional shapes. The most noticeable of the petals is called the labellum, or lip. It is often dramatically marked as an unmistakable landing strip to attract the specific insect the orchid has chosen as its pollinator. To lure their pollinators from afar, orchids use appropriately intriguing shapes, colors, and scents. At least 50 different aromatic compounds have been analyzed in the orchid family, each blended to attract one, or at most a few, species of insects or birds. Some orchids even change their scents to interest different insects at different times.

   Once the right insect has been attracted, some orchids present all sorts of one-way obstacle courses to make sure it does not leave until pollen has been accurately placed or removed. By such ingenious adaptations to specific pollinators, orchids have avoided the hazards of rampant crossbreeding in the wild, assuring the survival of species as discrete identities. At the same time they have made themselves irresistible to collectors.

A. a microscope

B. an obstacle course

C. an airport runway

D. a racetrack

   Orchids are unique in having the most highly developed of all blossoms, in which the usual male and female reproductive organs are fused in a single structure called the column. The column is designed so that a single pollination will fertilize hundreds of thousands, and in some cases millions, of seeds, so microscopic and light they are easily carried by the breeze. Surrounding the column are three sepals and three petals, sometimes easily recognizable as such, often distorted into gorgeous, weird, but always functional shapes. The most noticeable of the petals is called the labellum, or lip. It is often dramatically marked as an unmistakable landing strip to attract the specific insect the orchid has chosen as its pollinator. To lure their pollinators from afar, orchids use appropriately intriguing shapes, colors, and scents. At least 50 different aromatic compounds have been analyzed in the orchid family, each blended to attract one, or at most a few, species of insects or birds. Some orchids even change their scents to interest different insects at different times.

   Once the right insect has been attracted, some orchids present all sorts of one-way obstacle courses to make sure it does not leave until pollen has been accurately placed or removed. By such ingenious adaptations to specific pollinators, orchids have avoided the hazards of rampant crossbreeding in the wild, assuring the survival of species as discrete identities. At the same time they have made themselves irresistible to collectors.

A. orchids

B. birds

C. insects

D. species

   Orchids are unique in having the most highly developed of all blossoms, in which the usual male and female reproductive organs are fused in a single structure called the column. The column is designed so that a single pollination will fertilize hundreds of thousands, and in some cases millions, of seeds, so microscopic and light they are easily carried by the breeze. Surrounding the column are three sepals and three petals, sometimes easily recognizable as such, often distorted into gorgeous, weird, but always functional shapes. The most noticeable of the petals is called the labellum, or lip. It is often dramatically marked as an unmistakable landing strip to attract the specific insect the orchid has chosen as its pollinator. To lure their pollinators from afar, orchids use appropriately intriguing shapes, colors, and scents. At least 50 different aromatic compounds have been analyzed in the orchid family, each blended to attract one, or at most a few, species of insects or birds. Some orchids even change their scents to interest different insects at different times.

   Once the right insect has been attracted, some orchids present all sorts of one-way obstacle courses to make sure it does not leave until pollen has been accurately placed or removed. By such ingenious adaptations to specific pollinators, orchids have avoided the hazards of rampant crossbreeding in the wild, assuring the survival of species as discrete identities. At the same time they have made themselves irresistible to collectors.

A. complicated 

B. separate

C. inoffensive

D. functional

Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.

To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.

A. A writing has become too important in today's society.

B. speech is more basic to language than writing.

C. everyone who learns to speak must learn to writing.

D. all languages should have a written form.

Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.

To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.

A. “almost uncertainly”

B. “almost certainly”

C. “almost impossibly”

D. “almost doubtly”

Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.

To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.

A. is imperfect, but less than speech

B. represents speech, but not perfectly

C. developed from imperfect speech

D. is represented perfectly by speech

Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.

To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.

A. people who learn the rudiments of speech

B. people who speak many languages

C. intelligent people who couldn't write

D. severely handicapped children

Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.

To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.

A. “help somebody learn something by giving information about it”

B. “gain something by our own efforts or ability”

C. “become aware of something by hearing about it”

D. “develop a natural ability or quality so that it improves”

Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.

To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.

A. “think that something is more important”

B. “make something seem more important”

C. “think about something carefully”

D. “suggest that something is not important or valuable”

Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.

To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.

A. writing has more advantages than speech

B. speech is essential but writing has important benefits

C. speech conveys ideas less accurately than writing does

D. writing is more real than speech.

Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.

To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.

A. affirms the primacy of speech over writing

B. affirms the primacy of writing over speech

C. teaches its children to speak perfectly

D. keeps written records