Find synonym:
I'm totally exhausted after having finished successive assignments in only a week.

 

Choose the best answer:
John is studying hard. He doesn’t want to fail the exam.

Read the following passage and choose the best answer (A, B, C, D):
We live in a world of tired, sleep deprived people. In his book Counting Sheep, Paul Martin - a behavioral biologist - describes a society which is just too busy to sleep and which does not give sleeping the importance it deserves. Modern society has invented reasons not to sleep. We are now a 24/7 society where shops and services must be available all hours. We spend longer hours at work than we used to, and more time getting to work. Mobile phones and email allow us to stay in touch round the clock and late-night TV and the Internet tempt us away from our beds. When we need more time for work or pleasure, the easy solution is to sleep less. The average adult sleeps only 6.2 hours a night during the week, whereas research shows that most people need eight or even eight and a half hours’ sleep to feel at their best. Nowadays, many people have got used to sleeping less than they need and they live in an almost permanent state of “sleep debt”.  Until the invention of the electric light in 1879 our daily cycle of sleep used to depend on the hours of daylight. People would get up with the sun and go to bed at nightfall. But nowadays our hours of sleep are mainly determined by our working hours (or our social life) and most people are woken up artificially by an alarm clock. During the day caffeine, the world’s most popular drug, helps to keep us awake. 75% of the world’s population habitually consume caffeine, which up to a point masks the symptoms of sleep deprivation. What does a chronic lack of sleep do to us? As well as making us irritable and unhappy as humans, it also reduces our motivation and ability to work. This has serious implications for society in general. Doctors, for example, are often chronically sleep deprived, especially when they are on “night call”, and may get less than three hours’ sleep. Lack of sleep can seriously impair their mood, judgment, and ability to take decisions. Tired engineers, in the early hours of the morning, made a series of mistakes with catastrophic results. On our roads and motorways lack of sleep kills thousands of people every year. Tests show that a tired driver can be just as dangerous as a drunken driver. However, driving when drunk is against the law but driving when exhausted isn’t. As Paul Martin says, it is very ironic that we admire people who function on very little sleep instead of criticizing them for being irresponsible. Our world would be a much safer, happier place if everyone, whatever their job, slept eight hours a night  
2. The writer mentions the Internet in the passage as ______.

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 from 36 to 42.

It is estimated that by 2050 more than two-thirds of the world's population will live in cities, up from about 54 percent today. While the many benefits of organized and efficient cities are well understood, we need to recognize that this rapid, often unplanned urbanization brings risks of profound social instability, risks to critical infrastructure, potential water crises and the potential for devastating spread of disease. These risks can only be further exacerbated as this unprecedented transition from rural to urban areas continues.
 How effectively these risks can be addressed will increasingly be determined by how well cities are governed. The increased concentration of people, physical assets, infrastructure and economic activities mean that the risks materializing at the city level will have far greater potential to disrupt society than ever before.
 Urbanization is by no means bad by itself. It brings important benefits for economic, cultural and societal development. Well managed cities are both efficient and effective, enabling economies of scale and network effects while reducing the impact on the climate of transportation. As such, an urban model can make economic activity more environmentally-friendly. Further, the proximity and diversity of people can spark innovation and create employment as exchanging ideas breeds new ideas.
 But these utopian concepts are threatened by some of the factors driving rapid urbanization. For example, one of the main factors is rural-urban migration, driven by the prospect of greater employment opportunities and the hope of a better life in cities. But rapidly increasing population density can create severe problems, especially if planning efforts are not sufficient to cope with the influx of new inhabitants. The result may, in extreme cases, be widespread poverty. Estimates suggest that 40% of the world's urban expansion is taking place in slums, exacerbating socio-economic disparities and creating unsanitary conditions that facilitate the spread of disease.
 The Global Risks 2015 Report looks at four areas that face particularly daunting challenges in the face of rapid and unplanned urbanization: infrastructure, health, climate change, and social instability. In each of these areas we find new risks that can best be managed or, in some cases, transferred through the mechanism of insurance.

What can be inferred from the passage? 

Find mistake:
When he came, I watched a football match on TV.

Mark the letter A, B, C, or D on your answer sheet to indicate the undelined part that needs correction in each of the following questions:
It is said that George Washington was one of the first to realize how important tire building of canals would be to the nation’s development. In fact, before he became the President, he headed the first company in the United States to build a canal, which was to connect the Ohio and Potomac rivers. It was never completed, but it showed the nation the feasibility of canals. As the country expanded westward, settlers in western New York, Pennsylvania, and Ohio needed a means to ship goods. Canals linking natural waterways seemed to supply an effective method.
In 1791, engineers commissioned by the state of New York investigated the possibility of a canal between Albany on the Hudson River and Buffalo on Lake Eric to link the Great Lakes area with the Atlantic seacoast. It would avoid the mountains that served as a barrier to canals from the Delaware and Potomac rivers.
The first attempt to dig the canal, to be called the Eric Canal, was made by private companies but only a comparatively small portion was built before the project was halted for lack of funds. The cost of the prospect was estimated $5 million, an enormous amount for those days. There was some on-again-off-again federal funding, but this time the War of 1812 put an end to construction. In 1817, DeWitt Clinton was elected Governor of New York and persuaded the state to finance and build the canal. It was completed in 1825, costing S2 million more than expected.
The canal rapidly lived up to its sponsors’ faith, quickly paying for itself through tolls. It was far more economical than any other form of transportation at the time. It permitted trade between the Great Lake region and the East coast, robbing the Mississippi River of much of its traffic. It allowed New York to supplant Boston, Philadelphia, and other eastern cities as the chief center of both domestic and foreign commerce. Cities sprang up along the canal. It also contributed in a number of ways to the Norths victory over the South in the Civil War.
An expansion of the canal was planned in 1849. Increased traffic would undoubtedly have warranted its construction had it not been for the railroads.

The completion of the Eric Canal was financed by     _

Choose the word or phrase  A, B, C or D that best fits the blank space in the following passage:

"Face-to-face conversation is a two-way process: you speak to me, I reply to you and so on. Two-way (1)….. depends on having a coding System that is understood by both (2)….. and receiver, and an agreed convention about (3)…. the beginning and end of the (4)… . In speech, the coding System is the language like English or Spanish; the convention that one person speaks at a time may seem too obvious to (5)…. . In fact, the (6)…..that people use in conversations and meetings are often non- verbal. For example, lowering the pitch of voice may mean the end of a sentence; a Sharp intake of breath may signal the desire to (7)….. , catching the chairman’s (8)…. may indicate the desire to speak in a formal setting like a (9)….. , a clenched fist may indicate anger. When these (10)….. signals are not possible, more formal signals may be needed."

9. in a formal setting like a (9)….. , a clenched fist may indicate anger.

Read the following passage and choose the best answer (A, B, C, D):
Chichen-Itza is protected by the 1972 Federal Law on Monuments and Archaeological, Artistic and Historic Zones and was declared an archaeological monument by a presidential decree in 1986. The site remains open to the public 365 days of the year, and received a minimum of 3.500 tourists per day, a number which can reach 8.000 daily visitors in the high season. This means that the site needs constant maintenance and attention in order to avoid deterioration of its pre-hispanic fabric. Yucatan is the only state in Mexico where two institutions are involved in the management of archaeological sites: the National Institute of Anthropology and History (INAH), which is in charge of the care and conservation of the archaeological site, and the other is Board of Units of Cultural and Tourism Services of the State of Yucatan. Medium and long-term activities at Chichen-Itza, including investigation, conservation, thematic interpretation, administration and operation of the site, are addressed in the “Management Plan of the Pre-hispanic City of Chichen-Itza”. The purpose of the Plan is to articulate and coordinate the activities at the site, especially those geared towards the mise en valeur of the property and the generation of participation of the different sectors involved in the management, including the general public. No emergency plan exists for the site and there is no long term monitoring of the state of conservation, due to lack of personnel. This puts the site at risk from natural and anthropogenic disasters, as well as from longer term degradation. Threats like fire and lime stone erosion have been highlighted. Sustainable implementation of the defined planning tools and the allocation of resources to conservation and management are necessary means to ensure the conservation of the Outstanding Universal Value of the property in the long term.
5. According to paragraph 4, what is NOT mentioned as one of the jeopardies for the historical site?

Read the following passage and choose the best answer (A, B, C, D):
Nature photographer Joel Sartore is passionate about endangered species. He uses his  camera to make people aware of environmental problems. They tell the stories of animals that may disappear unless we work fast to save them.  Sartore’s latest project is called Photo Ark. The goal of the project is to make a photographic record of the world’s biodiversity. As Sartore says, “For many of Earth’s creatures, time is running out.”  When asked how he became interested in saving endangered species, Joel said “When I was a child, I read about Martha, the very last passenger pigeon. Martha died in 1914. I was shocked. In the past, there were 5 billion passenger pigeons – probably more than any other bird. But here was the last one, and there was no way to save it. How did we let this happen? I couldn’t understand it. I still feel the same way. I want to prevent this from ever happening again.” Photography is the best way to show problems to the world. It gets people to care about the problem. It’s not enough to just show pretty animals in a beautiful landscape. Now, we must show the threats to these animals as well. The good news is that there are many ways to publish stories and photographs on environmental issues. Self-publishing on the Web is one way to do this. Even nonprofessional photographers can help to make us aware of these problems
4. According to the passage, which of the following best describes Joel Sartore’s interest in saving endangered species?

Read the following passage and choose the best answer (A, B, C, D):
In 1903 the members of the governing board of the University of Washington in  Seattle engaged a firm of landscape architects, specialists in the design of outdoor environments - Olmsted Brothers of Brookline, Massachusetts - to advise them on an appropriate layout for the university grounds. The plan impressed the university officials, and in time many of its recommendations were implemented. City officials in Seattle, the largest city in the northwestern United States, were also impressed, for they employed the same organization to study Seattle’s public park needs. John Olmsted did the investigation and subsequent report on Seattle’s parks. He and his brothers believed that parks should be adapted to the local topography, utilize the area’s trees and shrubs, and be available to the entire community. They especially emphasized the need for natural, serene settings where hurried urban dwellers could periodically escape from the city. The essence of the Olmsted park plan was to develop a continuous driveway, twenty miles long, that would tie together a whole series of parks, playgrounds, and parkways. There would be local parks and squares too, but all of this was meant to supplement the major driveway, which was to remain the unifying factor for the entire system. In November of 1903 the city council of Seattle adopted the Olmsted Report, and it automatically became the master plan for the city’s park system. Prior to this report, Seattle’s park development was very limited and funding meager. All this changed after the report. Between 1907 and 1913, city voters approved special funding measures amounting to $4,000,000. With such unparalleled sums at their disposal, with the Olmsted guidelines to follow, and with the added incentive of wanting to have the city at its best for the AlaskaYukon-Pacific Exposition of 1909, the Parks Board bought aggressively. By 1913 Seattle had 25 parks amounting to 1,400 acres, as well as 400 acres in playgrounds, pathways, boulevards, and triangles. More lands would be added in the future, but for all practical purposes it was the great land surge of 1907-1913 that established Seattle’s park system
2. The word "engaged” in paragraph 1 is closest in meaning to ____

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.

The word "prosperity" in line 1 could be best replaced by which of the following?

A. B.     C. D. 

Read the following passage and choose the best answer for each blank.

In the western customs (26) _____ hands is the customary form of greeting, but in China a nod of the head or (27) _____ bow is sufficient. Hugging and kissing when greeting are uncommon. Business cards are often (28) _____ and yours should be printed in your own language and in Chinese. Also, it is more respectful to present your card or a gift or any other article using (29) _____ hands. The Chinese are (30) _____ applauders. You may be greeted with group clapping, even by small children. When a person is applauded in this practice it is the custom for that person to return the applause or a "thank you." When walking in public places, direct eye (31) _____ and staring is uncommon in the larger cities, especially in those areas accustomed to foreign visitors. (32) _____, in smaller communities, visitors may be the subject of much curiosity and therefore you may notice some stares. (33) _____ speaking, the Chinese are not a touch-oriented society, especially true for visitors. So, avoid (34) _____ or any prolonged form of body contact. Public displays of affection are very rare. On the other hand, you may note people of the same sex walking hand-in-hand, which is simply a gesture of friendship. Do not worry about a bit of pushing and shoving in stores or when groups board public buses or trains. In this case, (35) _____ are neither offered or expected. The Chinese will stand much closer than Westerners.

(35) _____

Read the following passage and choose the best answer (A, B, C, D)
Gender inequality remains an everyday reality for the world’s women and girls. It can begin right at the moment of birth and continue throughout the course of a woman’s life. Despite critical advances over the course of recent history, women in all countries and across all socioeconomic levels in society can face various forms of unfair treatment, including discrimination, harassment, domestic violence and sexual abuse. Other forms of abuse that are particularly prevalent in certain countries or cultural contexts include forced marriage, honor killings, deprivation of education, denial of land and property rights, and lack of access to work and to health care. Women may experience human rights abuses at different points in their working lives, including during recruitment, hiring, promotion and termination processes, as well as in daily interactions with colleagues and supervisors. Outside of the workplace, women are often particularly vulnerable to the social and environmental impacts of business activities. For example, in many developing countries, women and girls are primarily responsible for fetching and hauling water. When company operations contaminate local sources, it is they  who carry the burden of walking, often for hours, to the nearest substitute, which can prevent them from working or going to school. According to the UN Entity for Gender Equality and the Empowerment of Women, gender “refers to the social attributes and opportunities associated with being male and female and the relationships between women and men and girls and boys, as well as the relations between women and those between men. These attributes, opportunities and relationships are socially constructed and are learned through socialization processes.” Furthermore, gender equality “refers to the equal rights, responsibilities and opportunities of women and men and girls and boys. Equality does not mean that women and men will become the same but that women’s and men’s rights, responsibilities and opportunities will not depend on whether they are born male or female.” Women and girls comprise half of the planet’s population; their empowerment is essential in expanding economic growth and promoting social development in a sustainable way. Evidence from around the world shows that gender equality advancements have a ripple effect on all areas of sustainable development, from reducing poverty, hunger and even carbon emissions to enhancing the health, well-being and education of entire families, communities and countries. In fact, “Equality between women and men is seen both as a human rights issue and as a precondition for, and indicator of, sustainable people-centered development.”  
1. What does the passage mainly discuss?

Read the following passage and choose the best answer (A, B, C, D):
Perfectly smart adults feel intimidated by numbers and aren’t ashamed to say, “I hate math.” The new book “Math Art” could help change that by making the dreaded topic relevant and accessible to naturalists, artsy types, the philosophically inclined, and committed calculators alike. It illuminates an old lesson your math teachers probably tried to convey when you were a kid: Math dominates our lives even while we try with all our might to ignore it. In Math Art, released in April, science writer Ornes examines creative works inspired by math. It’s an aesthetically pleasing book with a delightfully tactile cover and satisfyingly thick and glossy pages that make it as fun to flip through as a fashion magazine. Chapters are dedicated to different concepts like pi, the golden ratio, equations in nature, and hyperbolic geometry. All of which may sound scary to the uninitiated but gain appeal when illustrated through sculpture, crochet, and painting. As Ornes explains in the introduction, math art isn’t new. Since ancient times, humans have visualized math in creative works. He argues that what is new is the mutual recognition that mathematicians and artists now show each other, increasingly gathering together at events dedicated to the intersection of aesthetics and numbers. “This is art by way of math and math by way of art, beauty at the crossroads,” Ornes writes.  His exploration begins with pi, the irrational mathematical constant 3.14159, plus some, ad infinitum. Pi, the ratio of the circumference of a circle to its diameter, represents mystery itself. Because the sequence never repeats, pi hints at the vastness of the universe. “It speaks to a world without bounds, since its digits go on forever,” Ornes explains. Pi is used for calculations in math and physics, and employed by math artist John Sims to make music, videos, drawings, paintings, quilts, clothing, and stories. Sims created and taught a math curriculum for students at the Ringling College of Art and Design in Sarasota, Florida, and has spent much of his career at the intersection of math and creativity. In Ornes’ book, he explains how he’s also used this fascination to connect with other people he might not otherwise meet, such as the Amish quilters who joined him to make pi quilts with each colored panel representing a number in the mathematical sequence.  
4. According to paragraph 2, what does Ornes include in his piece to get and keep the inexperienced engaged?

Find oppostite
Sadly, many non-disabled people have negative attitudes toward children with cognitive impairments in developing countries.

Read the following passage and choose the best answer (A, B, C, D):
The “balance of nature” is not an empty phrase. Nature provides a population to  occupy a suitable environment and cuts down surplus on population to fit the available food supply. One means of reducing surplus population is predators; others are parasites and diseases. Also, population density produces nervous disorders and even drivers animals to mass migrations, like the lemmings of Norway who plunge into the sea.  That predator populations increase to control other animals has long been known. Many years ago, the Hudsons Bay Company records revealed that the fox population went up and down about a year after the rabbit population had gone up and down.  Sometimes a situation occurs in which the predator population is reduced to a level below that which nature can readily replace. On Valcour Island in Lake Champlain (New York), a costly campaign resulted in the elimination of predatory animals only to have birds and small animals (including grouse and hares, popular game) increase for four years afterward. Then, lacking predator control, nature resorted to disease to cut down on these populations.  Jamaica had an example of natures persistence in providing animals for existing habits. Sugar planters, about 75 years ago, imported mongooses to control rats. The mongooses killed off the rats and, with plentiful food, multiplied. Rats became scarce and the mongooses ate lambs, puppies, and wildlife. Eventually, food became scarce and the mongooses’ population declined.
3. When predators control fails, nature brings animal population into balance by ____

Read the following passage and choose the best answer (A, B, C, D):
I started snowboarding in my late 20s and, knowing the dangers involved, my main aim has always been to get myself safely down the mountain in one piece. However, last year, I began to feel that my lack of courage was preventing me from improving. So I booked myself on the Snowcamp course in the town of Bourg-Saint-Maurice in the French Alps. There were 14 of us on the course and we stayed in a cheap guesthouse just outside the town. It was a basic-looking building made of local wood. There were strict rules about recycling our rubbish and all the electricity came from a nearby windmill. The facilities, however, went well beyond what I had expected for the price. There was a log fire, a heated boot room, fine balcony views and a menu that any chef would be proud of. Snowcamp was a good mix of holiday and group learning. Locations for lessons were chosen daily according to the snow conditions. Then we were put into three groups, depending on what skills people wanted to work on. Most of the time, I stayed on the main slopes. The teachers encouraged me to increase my speed and I even did some jumps. After a few days, a teacher called Johno persuaded me to take on a bigger challenge and try the deeper snow. The first 20 seconds of the lesson were fantastic, but then it got difficult. I kept sinking and then having to dig myself out. After 40 minutes, I felt like crying with tiredness and anger but I continued pushing myself and, when I got back on to the main slopes, I suddenly found everything far easier than before. It had been worth all the pain!  
4. The word "worth" in the passage is closest in meaning to

Mark the letter A, B, C, or D on your answer sheet to indicate the undelined part that needs correction in each of the following questions:
In the USA, the UK and many other countries, a lot of babies were born in the “baby boom” of the late 1940s and 1950s; after that the birth-rate fell. Baby boomers have now retired, or are approaching retirement, and this is causing headaches for many organizations: there are not enough people to succeed their top managers when they retire.
Does your organization have key staff who can’t easily be replaced? A CEO or financial director, perhaps, or a technical expert with knowledge that nobody else in the organization has. If your answer is “yes”, what will happen when they retire, or leave for another company? Will you wait until the last moment before looking for someone to replace them? Or is your organization thinking about likely future changes now, as it should be, and making plans, so that there is likely to be someone ready to replace the person leaving? If the answer is that you are planning ahead, your organization is carrying out succession planning.
Succession planning means looking inside the organization for “high-fliers” - current staff members with the potential to fill key positions - and planning the training, responsibilities and promotion they need, to make them ready when a senior vacancy occurs - which may not be for several years. The company benefits by being able to make an internal promotion when a key person leaves, and in the meantime it benefits by developing the skills of its high-fliers and encouraging them to stay. And the high-fliers benefit, because they achieve their full potential, a career is planned for them within the organization, and they can look forward to a senior post in time.
The training program planned for the high-fliers will help them to develop the leadership skills they need for more senior roles, skills such as planning long-term strategies. A career path is also planned, so that each high-flier moves into a number of different positions over a few years, to gain the experience and know ledge they need.
Sometimes a staff member is chosen as a potential successor to a particular senior manager, but a better method is for organizations to select a number of high-fliers, and prepare them for a range of senior roles. An organization can’t be certain when a particular senior manager will leave. Having a group of people being prepared fee top positions makes it easier to replace someone who leaves unexpectedly, and also means that there are other people available if a high-flier leaves the company.

What does the word “them” in the 3rd paragraph refer to?

Read the following passage and choose the best answer (A, B, C, D):
The International Monetary Fund (IMF) is an organization of 189 member countries.  It stabilizes the global economy in three ways. First, it monitors global conditions and identifies risks. Second, it advises its members on how to improve their economies. Third, it provides technical assistance and short-term loans to prevent financial crises. The IMF’s goal is to prevent these disasters by guiding its members. These countries are willing to give up some of their sovereign authority to achieve that aim.  The IMF has the rare ability to look into and review the economies of all its member countries. As a result, it has its finger on the pulse of the global economy better than any other organization. The IMF produces a wealth of analytical reports. It provides the World Economic Outlook, the Global Financial Stability Report, and the Fiscal Monitor each year. It also delves into regional and country-specific assessments. It uses this information to determine which countries need to improve their policies. Hence, the IMF can identify which countries threaten global stability. The member countries have agreed to listen to the IMF’s recommendations because they want to improve their economies and remove these threats.  Since the Mexican peso crisis of 1994–95 and the Asian crisis of 1997–98, the IMF has taken a more active role to help countries prevent financial crises. It develops standards that its members should follow. For example, members agree to provide adequate foreign exchange reserves in good times. That helps them increase spending to boost their economies during recessions. The IMF reports on members countries’ observance of these standards. It also issues member country reports that investors use to make well-informed decisions. That improves the functioning of financial markets. The IMF also encourages sustained growth and high living standards, which is the best way to reduce members’ vulnerability to crises.  The IMF provides loans to help its members tackle balance of payments problems, stabilize their economies, and restore sustainable growth. Because the Fund lends money, it’s often confused with the World Bank. The World Bank lends money to developing countries for specific projects that will fight poverty. Unlike the World Bank and other development agencies, the IMF does not finance projects. Traditionally, most IMF borrowers were developing countries. They had limited access to international capital markets due to their economic difficulties. An IMF loan signals that a country’s economic policies are on the right track. That reassures investors and acts as a catalyst for attracting funds from other sources. All that shifted in 2010 when the Eurozone crisis prompted the IMF to provide short-term loans to bail out Greece. That was within the IMF’s charter because it prevented a global economic crisis.  The role of the IMF has increased since the onset of the 2008 global financial crisis. In fact, an IMF surveillance report warned about the economic crisis but was ignored. As a result, the IMF has been called upon more and more to provide global economic surveillance. It’s in the best position to do so because it requires members to subject their economic policies to IMF scrutiny. Member countries are also committed to pursuing policies that are conducive to reasonable price stability, and they agree to avoid manipulating exchange rates for unfair competitive advantage.
1. What does the passage mainly discuss?

Choose the best answer:
Houses in Hoi An were made _________ wood and their pillars were carved with ornamental designs.

Read the following passage and choose the best answer (A, B, C, D):
Far from being barren wastelands, deserts are biologically rich habitats with a vast  array of animals and plants that have adapted to the harsh conditions there. Some deserts are among the planet’s last remaining areas of total wilderness. Yet more than one billion people, one-sixth of the Earth’s population, actually live in desert regions.  Deserts cover more than one fifth of the Earth’s land, and they are found on every continent. A place that receives less than 10 inches (25 centimeters) of rain per year is considered a desert. Deserts are part of a wider classification of regions called “dry lands.” These areas exist under a moisture deficit, which means they can frequently lose more moisture through evaporation than they receive from annual precipitation.  And despite the common conceptions of deserts as dry and hot, there are cold deserts as well. The largest hot desert in the world, northern Africa’s Sahara, reaches temperatures of  up to 122 degrees Fahrenheit (50 degrees Celsius) during the day. But some deserts are always cold, like the Gobi desert in Asia and the desert on the continent of Antarctica. Others are mountainous. Only about 10 percent of deserts are covered by sand dunes. The driest deserts get less than half an inch (one centimeter) of precipitation each year, and that is from condensed fog not rain.  Desert animals have adapted ways to help them keep cool and use less water. Camels, for example, can go for days without food and water. Many desert animals are nocturnal, coming out only when the brutal sun has descended to hunt. Some animals, like the desert tortoise in the south-western United States, spend much of their time underground. Most desert birds are nomadic, crisscrossing the skies in search of food. Because of their very special adaptations, desert animals are extremely vulnerable to introduced predators and changes to their habitat.  Some of the world’s semi-arid regions are turning into desert at an alarming rate. This process, known as “desertification,” is not caused by drought, but usually arises from the demands of human populations that settle on the semi-arid lands to grow crops and graze animals. The pounding of the soil by the hooves of livestock may degrade the soil and encourage erosion by wind and water.
7. What subject is this text probably found in?