Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
After two decades of growing student enrollments and economic prosperity, business schools in the United States have started to face harder times. Only Harvard's MBA School has shown a substantial increase in enrollment in recent years. Both Princeton and Stanford have seen decreases in their enrollments. Since 1990, the number of people receiving Masters in Business Administration (MBA) degrees, has dropped about 3 percent to 75,000, and the trend of lower enrollment rates is expected to continue.
There are two factors causing this decrease in students seeking an MBA degree. The first one is that many graduates of four-year colleges are finding that an MBA degree does not guarantee a plush job on Wall Street, or in other financial districts of major American cities. Many of the entry-level management jobs are going to students graduating with Master of Arts degrees in English and the humanities as well as those holding MBA degrees. Students have asked the question, "Is an MBA degree really what I need to be best prepared for getting a good job?" The second major factor has been the cutting of American payrolls and the lower number of entry-level jobs being offered. Business needs are changing, and MBA schools are struggling to meet the new demands.

What is the main focus of this passage?

Read the following passage and choose the best answer (A, B, C, D):
Alzheimer's disease impairs a person's ability to recall memories, both distant and as a few hours before. Although there is no yet a cure for the illness, there may be hope for a cure with a protein called nerve growth factor. The protein is produced by nerve cells in the same region of the brain where Alzheimer's occurs. Based on this relationship, scientists from the University of Lund in Sweden and the University of California at San Diego designed an experiment to test whether doses of nerve growth factor could reverse the effects of memory loss caused by Alzheimer's. Using a group of rats with impaired memory, the scientists gave half of the rats doses of nerve growth factor while giving the other half a blood protein as a placebo, thus creating a control group. At the end of the four-week test, the rats given the nerve growth factor performed equally to rats with normal memory abilities. While the experiment do not show that nerve growth factor can stop the general process of deterioration caused by Alzheimer's, they do show potential as a means to slowing the process significantly.
10. The relationship between nerve growth factor and a protein is similar to the relationship between Alzheimer's and

Read the following passage and choose the best answer (A, B, C, D):
New technology helped cities grow. Elevated trains carried passengers over (1) ____ streets. In 1887, the first electric streetcar system opened in Richmond, Virginia. Ten years later, the nation’s first electric subway trains began running beneath the streets of Boston. Public transportation gave (2) ____ to suburbs, living areas on the outskirts of a city. People no longer had to live in cities to work in cities. Steel bridges also accelerated suburban growth. The Brooklyn Bridge, completed in 1883, (3) ____ the city center in Manhattan to outlying Brooklyn. As a result, New York City was able to spread out to house its growing population. Cities began to expand upward as well as outward. In 1885, architects in Chicago constructed the first 10-story building. People called it a “skyscraper” because its top seemed to touch the sky. By 1900, (4) ____ skyscrapers up to 30 stories high towered over cities. Electric elevators whisked office workers to the upper floors. As cities grew outward from their old downtown sections, living patterns changed. Many cities took on a similar shape. Poor families crowded (5) ____ the oldest sections at the city’s center. Middle-class people lived farther out in row houses or new apartment buildings. The rich built fine homes on the outskirts of the city.

Read the following passage and choose the best answer (A, B, C, D):
The cities in the United States have been the most visible sponsors and beneficiaries  of projects that place art in public places. They have shown exceptional imagination in applying the diverse forms of contemporary art to a wide variety of purposes. The activities observed in a number of “pioneer” cities sponsoring art in public places - a broadening exploration of public sites, an increasing awareness among both sponsors and the public of the varieties of contemporary artistic practice, and a growing public enthusiasm - are increasingly characteristic of cities across the country. With many cities now undergoing renewed development, opportunities are continuously emerging for the inclusion or art in new or renewed public environments, including buildings, plazas, parks, and transportation facilities. The result of these activities is a group of artworks that reflect the diversity of contemporary art and the varying character and goals of the sponsoring communities.  In sculpture, the projects range from a cartoonlike Mermaid in Miami Beach by Roy Lichtenstein to a small forest planted in New York City by Alan Sonfist. The use of murals followed quickly upon the use of sculpture and has brought to public sites the work of artists as different as the realist Thomas Hart Benton and the Pop artist Robert Rauschenberg. The specialized requirements of particular urban situations have further expanded the use of art in public places: in Memphis, sculptor Richard Hunt has created a monument to Martin Luther King, Jr., who was slain there; in New York, Dan Flavin and Bill Brand have contributed neon and animation works to the enhancement of mass transit facilities. And in numerous cities, art is being raised as a symbol of the commitment to revitalize urban areas.  By continuing to sponsor projects involving a growing body of art in public places, cities will certainly enlarge the situations in which the public encounters and grows familiar with the various forms of contemporary art. Indeed, cities are providing artists with an opportunity to communicate with a new and broader audience. Artists are recognizing the distinction between public and private spaces, and taking that into account when executing their public commissions. They are working in new, often more durable media, and on an unaccustomed scale.
5. It can be inferred from the passage that the city of Memphis sponsored a work by Richard Hunt because the city authorities believed that ____.

Choose the best answer:
Your house needs ...............

Read the following passage and choose the best answer (A, B, C, D):
Adharanand Finn is a British journalist and a keen runner. Recently, he did the Fluorspar run in Kenya with a group of top Kenyan athletes. Here is the story he told the press after the event. The route of the Fluorspar run is exactly 21 km long and is uphill from start to finish. When I arrived at the start of the run at the bottom of the hill, the morning sun was up, and it was already hot. The ten athletes and I stood together for a group photograph and then immediately started our run up to the top. Most of the athletes who live in this part of Kenya have done it at least once. After about five minutes, I was already starting to fall behind other runners. I’ve never been that good at hill climbing, so I always knew I’d find it thorny. ‘Sure and steady,’ I told myself as I ran along, avoiding the biggest stones and trying to take the shortest line up the hill. But whenever I looked up, the others were further ahead, until soon they disappeared completely. At first I felt fine, but towards the end I began to feel a bit weak and strange. I don’t know now if I was imagining things but the people I passed, who were travelling down the road, seemed to be laughing at me. Finally, I reached the top. The rest of the runners were sitting on the grass, drinking lemonade and eating peanuts and boiled eggs. It took me one hour and fifty eight minutes, which is not bad at all. The others told me kindly that anyone who can run it in under two hours is very strong. They completed it much faster, in around one hour 30 minutes. I honestly have no idea how they do it.  
5. What is the writer doing in this text?

Biofuels and the Environment

Leading investors have joined the growing chorus of concern about governments and companies rushing into producing biofuels as a solution for global warming, saying that many involved in the sector could be jeopardizing future profits if they do not consider the long-term impact of what they are doing carefully.

It is essential to build sustainability criteria into the supply chain of any green fuel project in order to ensure that there is no adverse effect on the surrounding environment and social structures. The report produced by the investors expresses concern that many companies may not be fully aware of the potential pitfalls in the biofuel sector.

Production of corn and soya beans has increased dramatically in the last years as an eco-friendly alternative to fossil fuels but environmental and human rights campaigners are worried that this will lead to destruction of rain forests. Food prices could also go up as there is increased competition for crops as both foodstuffs and sources of fuel. Last week, the UN warned that biofuels could have dangerous side effects and said that steps need to be taken to make sure that land converted to grow biofuels does not damage the environment or cause civil unrest. There is already great concern about palm oil, which is used in many foods in addition to being an important biofuel, as rain forests are being cleared in some countries and people driven from their homes to create palm oil plantations.

An analyst and author of the investors' report say that biofuels are not a cure for climate change but they can play their part as long as governments and companies manage the social and environmental impacts thoroughly. There should also be greater measures taken to increase efficiency and to reduce demand.

The increased production of palm oil _____.

Read the following passage and choose the best answer (A, B, C, D):
Desertification is creating additional challenges to the survival of endangered animal species in India, according to a senior wildlife official who attended the 14th Conference of Parties (COP14) to the United Nations Convention to Combat Desertification (UNCCD) in New Delhi. A few days earlier, at COP14 in New Delhi, Dr Chandra had said that the statistics on species extinction have been derived from a database of more than 5.6 million specimens, which have lived across India and the neighbouring countries since before independence. The deteriorating pattern in the species’ distribution in geo-special platforms over the past 100 years clearly highlights the concerning impact of deforestation and desertification. Land degradation threatens species like the Great Indian Bustard, which is classified as “critically endangered” by the International Union for Conservation of Nature (IUCN). The Weather Channel India got in touch with Dr Chandra, who said that less than 150 Great Indian Bustards are alive today. “Desertification and land degradation are among the 20-30 risk factors to the survival of Great Indian Bustards,” Dr Chandra told Weather.com. In simple terms, desertification is a process wherein fertile land becomes unusable, typically as a result of a long drought, deforestation, salinisation, intensive agricultural practices, and the excessive usage of insecticides, pesticides and chemicals. Desertification leads to hazardous effects on not just animals, but also on the food chain and the overall biodiversity—right from microscopic organisms to human beings. Deforestation has affected over 30% of the land in India due to over-cultivation, soil erosion and depletion of wetlands. Along with India, the planet as a whole currently stares at the fast-growing threat of land degradation  
5. The word “depletion” in paragraph 5 is closest in meaning to ______

A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometres in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the tune it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word "radar" in fact gets its name from the term "radio detection and ranging". "Ranging" is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots radar is essential for air traffic control tracking ships at sea, and for tracking weather Systems and storms.

According to the passage, the distance between a radar set and an object can be determined by   

Read the following passage and choose the best answer (A, B, C, D):
Adharanand Finn is a British journalist and a keen runner. Recently, he did the Fluorspar run in Kenya with a group of top Kenyan athletes. Here is the story he told the press after the event. The route of the Fluorspar run is exactly 21 km long and is uphill from start to finish. When I arrived at the start of the run at the bottom of the hill, the morning sun was up, and it was already hot. The ten athletes and I stood together for a group photograph and then immediately started our run up to the top. Most of the athletes who live in this part of Kenya have done it at least once. After about five minutes, I was already starting to fall behind other runners. I’ve never been that good at hill climbing, so I always knew I’d find it thorny. ‘Sure and steady,’ I told myself as I ran along, avoiding the biggest stones and trying to take the shortest line up the hill. But whenever I looked up, the others were further ahead, until soon they disappeared completely. At first I felt fine, but towards the end I began to feel a bit weak and strange. I don’t know now if I was imagining things but the people I passed, who were travelling down the road, seemed to be laughing at me. Finally, I reached the top. The rest of the runners were sitting on the grass, drinking lemonade and eating peanuts and boiled eggs. It took me one hour and fifty eight minutes, which is not bad at all. The others told me kindly that anyone who can run it in under two hours is very strong. They completed it much faster, in around one hour 30 minutes. I honestly have no idea how they do it.  
2. What does the writer say about the last part of the run?

Choose the best answer:
The party was ............... I had expected.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions:
The ruined temples of Angkor are perhaps one of the most impressive Seven Wonders of the World. Located in modern day Cambodia near Lake Tonle Sap, the largest freshwater lake in Asia, Angkor was the seat of power for the Khmer Empire for the ninth to the fifteenth century. The ruins of Angkor are documented as some of the most impressive ones in the world, rivaling the pyramids of Giza in Egypt. Why this mighty civilization died out is a question that archaeologists are now only beginning to ponder. The answer, it turns out, may be linked with the availability of fresh water.
One possible explanation for the downfall of the Khmer Empire has to do with the inhabitant’s irrigation system. The temples and palaces of Angkor were constructed around a series of artificial reservoirs and canals which were annually flooded to capacity by the Mekong River. Once filled, they were used to irrigate the surrounding paddies and farmland during the course of the year. Farmers were completely dependent on the water for their crucial rice crop. Without consistent irrigation, the farmers would have been unable to maintain functional crop production.
Scientists speculate that toward the end of the Khmer Empire the hydraulic system of the reservoirs and canals broke down. The construction of hundreds of sandstone temples and palaces required an enormous amount of physical labor. In addition, as the capital of Khmer Empire, Angkor contained upwards of one hundred thousand people who resided in and around Angkor. In order to feed so many people, the local farmers were driven to grow food more quickly and more efficiently. After centuries of continual use, the irrigation system was pushed beyond its capacity. Soil erosion, nutrient depletion, and loss of water led to decrease in the food supply. With the less food available, the people of Angkor slowly began to migrate to other parts of Cambodia, thus leaving the marvelous city of Angkor to be swallowed by the jungle. Therefore, it is speculated that the Khmer Empire may have fallen victim to its own decrepit infrastructure.

The word “artificial” in paragraph 2 is closest in meaning to

Read the following passage and choose the best answer (A, B, C, D):
Sophia is a humanoid robot developed by Hong Kong-based company Hanson Robotics. She has been designed to learn and adapt to human behavior and work with humans, and has been interviewed around the world. In October 2017, she became a Saudi Arabian citizen, the first robot to receive citizenship of a country. According to herself, Sophia was activated on April 19, 2015. She is modeled after actress Audrey Hepbum,and is known for her human-like appearance and behavior compared to previous robotic variants. According to manufacturer, David Hanson, Sophia has artificial intelligence, visual data processing and facial recognition. Sophia also imitates human gestures and facial expressions and is able to answer certain questions and to make simple conversations on predefined topics (e.g. on the weather). The robot uses voice recognition technology from Alphabet Inc. (parent company of Google) and is designed to get smarter over time. Sophia’s intelligence software is designed by SingularityNET. The AI program analyses conversations and extracts data that allows her to improve responses in the future. It is conceptually similar to the computer program ELIZA, which was one of the first attempts at simulating a human conversation. Hanson designed Sophia to be a suitable companion for the elderly at nursing homes, or to help crowds at large events or parks. He hopes that she can ultimately interact with other humans sufficiently to gain social skills. Sophia has been interviewed in the same manner as a human, striking up conversations with hosts. Some replies have been nonsensical, while others have been impressive, such as lengthy discussions with Charlie Rose on 60 Minutes. In a piece for CNBC, when the interviewer expressed concerns about robot behavior, Sophia joked that he had “been reading too much Elon Musk, and watching too many Hollywood movies”. Musk tweeted that Sophia could watch The Godfather and suggested “What’s the worst that could happen?”. On October 11, 2017, Sophia was introduced to the United Nations with a brief conversation with the United Nations Deputy Secretary-General, Amina J. Mohammed. On October 25, at the Future Investment Summit in Riyadh, she was granted Saudi Arabian citizenship, becoming the first robot ever to have a nationality. This attracted controversy as some commentators wondered if this implied that Sophia could vote or marry, or whether a deliberate system shutdown could be considered murder. Social media users used Sophia’s citizenship to criticize Saudi Arabia’s human rights record. 
7. The word “this” in the last paragraph refers to_______

Read the following passage and choose the best answer (A, B, C, D):
IN ONE CUBIC FOOT In any environment - forest, mountain or water - you always see big animals first: birds, mammals, fish. But under your feet, on land or in water there are many smaller organisms: insects, tiny plants, miniature sea creatures. They seem unimportant, but, in fact, these sea creatures and ground dwellers are “the heart of life on the Earth”, say naturalist E.O Wilson. Without them, our world would change dramatically. Most organisms on the Earth live on the ground or just below it. Here, they are part of an important cycle. Plants and animals fall to the ground when they die. Later, tiny insects and other organisms break down the dead plant and animal material. This process eventually returns nutrients to the soil and give plants energy. Plants can then help to maintain healthy environment for humans and other animals. Despite their importance, scientists know very little about most ground organisms. To learn more, photographer David Liittschwager went to different places around the world, including a forest, a river, a mountain, and a coral reef. In each place, he put a green 12-inch cube on the ground or in the water. Then he and his team counted and photographed the organisms that lived in or moved through the cube. Often they discovered hundreds, some only a millimeter in size. “It was like finding little germs”, he says. In the coral reef in French Polynesia, he saw thousands of creatures in the cube and photographed 600. The team identified as many as possible, but it was difficult. Many of the animals they found were new species.  
1. Another tile for the passage could be?

Read the following passage and choose the best answer (A, B, C, D):
Saving the planet is very much in vogue. It’s also in Harper’s Bazaar, Elle and Mademoiselle. It’s the message on fashion runways, in marketing strategies, in jewelry and accessory designs, on shopping bags and totes, in advertisements and on price tags. A naked fashion model wearing a hat of birch branches and lichen, as shown in Vogue this month, may not be everyone’s idea of environmental awareness. But the pervasiveness of ecological themes in the images and marketing of fashion is undeniable. It is also somewhat paradoxical. The fashion industry, whose driving philosophy involves encouraging consumers to discard the old and embrace the new, is now trying to push itself to the forefront of efforts to conserve and preserve. The environmental theme in fashion began as wispy touches and graphic exhortations in designer collections, not as some well-thought-out strategy of “green” marketing in which the environmental advantages of a product become part of the sales approach. Tendrils of ivy dangled from the ceiling at a Paris fashion show; a carpet of grass covered a runway in New York; models marched along in T-shirts or carrying signs all bearing slogans like “Clean Up or Die,” “Save the Sphere,” and “Environmental Protection Agents”.  The environmental spin on fashion has now moved into the mass market, where ‘’clothes with conscience’‘ make an extra tug at the buyer’s self-image. Bonjour, a jeans and sportswear company based in New York, has embarked on a program to ’‘change the individual’s outlook toward saving the environment’’ through educational tags. This summer, the first wave of what Bonjour executives said would be 50 million fashion items a year are to arrive in stores carrying tags with environmental tips from how to save water to how to reduce pollutants. Whether these tributes to nature will benefit the environment or even raise environmental awareness, with concomitant changes in individual behavior, is not clear. There is some skepticism. Professor Ewen says the new environmental symbolism should be viewed as part of an overall change in America’s economy, from one built on industrial production of hard goods to one based on “pure representation”. “Going back to fashion, the environment has become a commercial cliche separated from real concerns. What can be attached to this year’s fashion is merely the symbolism of environmental sanity.” 
8. Which of the following can be inferred from the passage?

Choose the best answer:
Jack always wants to achieve high goals. He’s so ___________.

Most Americans still get married at some point in their lives, but even that group is shrinking. Among current generations of adult American - starting with those bom in 1920s - more than 90 percent have married or will marry at some point in their lives. However, based on recent patterns of marriage and mortality, demographers calculate that a growing share of the younger generations are postponing marriage for so long that an unprecedented number will never marry at all.

More Americans are living together outside of marriage. Divorced and widowed people are waiting longer to remarry. An increasing number of single women are raising children. Put these trends together with our increasing life expectancy, and the result is inevitable. Americans are spending a record low proportion of their adult lives married.

Married rates for unmarried men and women have dropped from their post-195Os high to record lows. Part of this fall is due to the change in the age at which people first marry. The median age at first marriage is the age by which half the men or women who will ever marry have done so. It fell almost continuously from the time it was first measured, in 1890, at 22.0 years for women and 26.1 for men, to a low of 20.3 for women and 22.6 for men between 1947 and 1962. Since then, it has risen at a rapid pace, to a record high for 23.8 for women and 26.2 for men in 1994.

The length of time between marriages is also increasing, and more divorced people are choosing not to remarry. In 1990, divorced men had waited an average of 3.8 years before remarrying, and divorced women had waited an average of 3.5 years, an increase of more than one year over the average interval in 1970.

Data on cohabitation and unmarried childbearing suggest that marriage is becoming less relevant to Americans. 2.8 million of the nation's households are unmarried couples, and one-third of them are caring for children, according to the Census Bureau.

Between 1890 and the 1950s, the age at which men first married    

Read the following passage and choose the best answer (A, B, C, D):
Many people believe the glare from snow causes snow-blindness. Yet, dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snowblindness, when exposed to several hours of “snow light”. The United States Army has now determined that the glare from snow does not cause snow-blindness in troops in a snow-covered country. Rather, a man’s eyes frequently find nothing to focus on in a broad expanse of a snow-covered area. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscles ache. Nature balances this annoyance by producing more and more liquid which covers the eyeballs. The liquid covers the eyeballs in increasing quantity until vision blurs. And the result is total, even though temporary, snow-blindness. Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark-colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop searching through the snow-blanketed landscape. By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost: In this way the problem of crossing a solid white area is overcome
4. The underlined word “they” in the third paragraph refers to ____

Read the following passage and choose the best answer (A, B, C, D):
Generation gap refers to a vast difference in cultural norms between a younger generation and their elders. It’s a distressing thing for the phenomenon (1) ____ occurs around the world. The (2) ____ of communication, different views on certain problems and different attitudes towards life may cause the generation gap or even widen it. First, one of the major factors for this misunderstanding between two generations is that parents and children lack communication. Young people (3) ____ reveal their feelings to their parents, and often complain that their parents are out of (4) ____ with modern days, that they are dominant, that they do not trust their children to deal with crises, and that they talk too much about certain problems. So when young people meet some problems, they would rather (5) ____ to their classmates or their friends for help. The lack of communication widens the generation gap Another factor is that parents and their children see almost everything from different (6) ____. Take choosing career as an example. Parents generally believe it is their responsibility to plan the career for their children. Some hope their children will (7) ____ professions that will bring them greatest prestige and economic benefits. Some hope children will have a stable job with a regular income. But the youth may think they should be free to (8) ____ their own decisions as to their future career. Young people explain that true success is not a matter of money or position, instead, it is a matter of self-fulfillment. Finally, with the change of the world over decades, the attitude of the young has altered too. There are differences in (9) ____ matters as musical tastes, fashions, drug use, sex and politics between the young people and their elders. Nowadays long hair on young males is viewed as fashion by the young, but it is frequently considered a shocking act of rebellion against (10) ____ norms by parents

Read the following passage and choose the best answer (A, B, C, D):
In Viet Nam festivals often take place during the three months in spring and in autumn when people have a lot of leisure time. In addition, the climate in spring and autumn is especially suitable for holding festivals and for festivals goers to enjoy. Traditional festivals constitute a form of cultural activities, a spiritual product which the people have created and developed during the course of history. From generation to generation, the Vietnamese people preserve the fine tradition of “remembering the source while drinking water.” Festivals are events which represent this tradition of the community as well as honor the holy figures named as “gods” – the real persons in national history or legendary persons. The images of gods converge the noble characteristics of mankind. They are national heroes who fought against foreign invaders, reclaimed new lands, treated people, fought against natural calamities, or those legendary characters who affect the earthly life. Accordingly, first and foremost, festivals are events when people pay tribute to divinities that rendered merits to the community and the nation. These are occasions when people come back to either their natural or national roots, which form a sacred part in their mind. Furthermore, festivals represent the strength of the commune or village, the local region or even the whole nation. Worshipping the same god, the people unite in solidarity to overcome difficulties, striving for a happy and wealthy life. Moreover, festivals display the demand for creativity and enjoyment of spiritual and material cultural values of all social strata. Festivals become a form of education under which fine traditional moral values can be handed from one generation to the next in a unique way of combining spiritual characters with competition and entertainment games. Festivals are also the time people can express their sadness and worries in a wish that gods might bestow favor on them to help them strive for a better life.  
5. What is the best title of the passage?

Read the following passage and choose the best answer (A, B, C, D):
The first two decades of this century were dominated by the microbe hunters. These hunters had tracked down one after another of the microbes responsible for the most dreaded scourges of many centuries: tuberculosis, cholera, diphtheria. But there remained some terrible diseases for which no microbe could be incriminated: scurvy, pellagra, rickets, beriberi. Then it was discovered that these diseases were caused by the lack of vitamins, a trace substance in the diet. The diseases could be prevented or cured by consuming foods that contained the vitamins. And so in the decades of the 1920’s and 1930’s, nutrition became a science and the vitamin hunters replaced the microbe hunters. In the 1940’s and 1950’s, biochemists strived to learn why each of the vitamins was essential for health. They discovered that key enzymes in metabolism depend on one or another of the vitamins as coenzymes to perform the chemistry that provides cells with energy for growth and function. Now, these enzyme hunters occupied center stage. You are aware that the enzyme hunters have been replaced by a new breed of hunters who are tracking genes – the blueprints for each of the enzymes – and are discovering the defective genes that cause inherited diseases – diabetes, cystic fibrosis. These gene hunters, or genetic engineers, use recombinant DNA technology to identify and clone genes and introduce them into bacterial cells and plants to create factories for the massive production of hormones and vaccines for medicine and for better crops for agriculture. Biotechnology has become a multibilliondollar industry. In view of the inexorable progress in science, we can expect that the gene hunters will be replaced in the spotlight. When and by whom? Which kind of hunter will dominate the scene in the last decade of our waning century and in the early decades of the next? I wonder whether the hunters who will occupy the spotlight will be neurobiologists who apply the techniques of the enzyme and gene hunters to the funtions of the brain. What to call them? The head hunters. I will return to them later.
2. The word “incriminated’ in the first paragraph is closest in meaning to: