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

The Middle East and North Africa are one of the driest regions on earth. Nearly two-thirds of the region is desert. The Sahara Desert of northern Africa is the largest desert in the world. Desert air (26) ____ little moisture, so few clouds form over the land. Without clouds to block the sun, temperatures may reach as (27) ____ as 125°F during the day. At night, without the clouds to contain the heat, the temperature can fall to as low as 125°F. Extreme temperatures (28) ____ with little rainfall make desert life difficult for people, plants, and animals. (29) ____, some life forms have adapted to even the most severe desert (30) ____, Camels are able to survive long periods without food or water. Many desert plants have long, shallow (31) ____ systems. This allows the plants to reach out to collect water over great distances. Other desert plants have taproots. Taproots grow very deep (32) ____ they can tap sources of underground water. Plant life in the desert is usually spread out over great distances. This is (33) ____ deserts are often described as barren, or lifeless. When many people think of a desert they often think of endless miles of hot sand, but a desert does not have to be hot or sandy. Most of the land of the Middle East and North Africa is hot, dry desert land, (34) ____ some deserts look very different. Most of Antarctica is a desert but there is no sand on the continent and the climate of Antarctica is (35) ____ coldest on earth.

(33) ____

Choose the item among A, B, C or D that best answers the question about the passage:

"The deserts of the world are not all covered with sand. Many of them have surfaces of rock or clay or small stones. They are not flat, either; they often have high hills and deep valleys. There is some plant life in many parts of the desert. There is little rain in the desert, but it does fall often enough for most plants. The deserts of the world are not uninhabited. People also live outside oases, but these people are not farmers. They have camels, goats, donkeys, sheep, etc. These animals can live on the desert plants and do not need much water.
 The people of the desert have to move constantly from place to place, they must always look for grass or desert plants for their animals. They usually live in tents. When there is no more food for their animals, they fold up their tents, put them on their camels and donkeys, and move to another place. In good years, when there is enough food for their animals, they trade their skins and their goats and camel hairs with the people of oases for wheat and fruit. But in bad years, when there is not enough food for their animals, the people of the desert would attack the oases people. But they are also hospitable. No man in the desert would ever refuse to give a stranger food and water."

1. According to the passage, deserts are mostly made up of ……

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.
There are many theories of aging, but virtually all fall into the category of hypotheses with a minimum of supporting evidence. One viewpoint is that aging occurs as the body's organ systems become less efficient. Thus failures in the immune system, hormonal system, and nervous system could all produce characteristics that we associate with aging. Following a different vein, many current researchers are looking for evidence at the cellular and sub cellular level. It has been shown that cells such as human fibroblasts (generalized tissue cells) grown in culture divide only a limited number of times and then die. Only cancer cells seem immortal in this respect. Fibroblast cells from an embryo divide more times than those taken from an adult. Thus some researchers believe that aging occurs at the cellular level and is part of the cell's genetic makeup. Any event that disturbs the cell's genetic machinery such as mutation, damaging chemicals in the cell's environment, or loss of genetic material, could cause cells to lose their ability to divide and thus bring on aging. Other theories of aging look at different processes. 
Chronological aging refers to the passage of time since birth and is usually measured in years. While chronological age can be useful in estimating the average status of a large group of people, it is a poor indicator of an individual person's status because there is a tremendous amount of variation from one individual to the next in regard to the rate at which biological age changes occur. For example, on the average, aging results in people losing much of their ability to perform strenuous activities, yet some elderly individuals are excellent marathon runners.
Another type of aging is cosmetic aging, which consists of changes in outward appearance with advancing age. This includes changes in the body and changes in other aspects of a person's appearance, such as the style of hair and clothing, the type of eyeglasses, and the use of a hearing aid. Like chronological aging, it is frequently used to estimate the degree to which other types of aging have occurred. However, it is an inaccurate indicator for either purpose because of variation among individuals and because a person's appearance is affected by many factors that are not part of aging, including illness, poor nutrition, and exposure to sunlight.

It can be inferred from the passage that fibroblast cells_________,

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

"The Southwestern States of the United States suffered one of the worst droughts in their history from 1931 to 1938. The drought (1)…. the entire country. Few food crops could be grown. Food became (2)…., and prices went up (3)….  the nation. Hundreds of families in the Dust Bowl region had to be moved to farms in other areas with the help of the federal government. In 1944, drought brought great damage to (4)…. all Latin America. The drought moved to Australia and then to Europe, (5)…. it continued throughout the summer of 1945. From 1950 to 1954 in the United States, the Southwest suffered a (6)….. drought Hundreds of cattle ranches had to ship their cattle to other regions because (7)… lands had no grass. The federal government again (8)….. an emergency drought-relief program. It offered farmers (9)…. credit and seed grains (10)… low prices."

10. and seed grains (10)… low prices

Read the following passage and choose the correct answer in each sentence.

Last week, I had an occasion to — 131 — with Mr. Harries and Mr. Grava from your customer support team. I came to the office with a series of questions for a research project that I am working on. The information I needed tumed out to be more — 132— than I had anticipated but for awhile, your team was very patient, courteous and professional. — 133 —. It is clear that your customer service is one of the keys to your company’s success. I want you to know how much I — 134 — the assistance.

131..................

Fill in each numbered blank with one suitable word or phrase.

Desert biomes are the (1) _____ of all the biomes. In fact, the most important characteristic of a desert is that it receives very little (2) _____. Most deserts receive less than 300 mm a year compared (3) _______ rainforests, which receive over 2,000 mm. That means that the desert only gets 10 percent of the rain that a rainforest gets! The temperature in the desert can (4) _____ drastically from day to night because the air is (5) _____ dry that heat escapes rapidly at night. The daytime temperature averages 38°C (6) _____ in some deserts it can get down to -4°C at night. The temperature also varies greatly depending on the (7) _____ of the desert. Since desert conditions are so severe, the plants that live there need to have (8) _____ to compensate for the lack of water. Some plants, such as cacti, (9) _____ water in their stems and use it very slowly, while others like bushes conserve water by growing few leaves or by having large root systems to gather water or few leaves. Some desert plant species have a short life cycle of a few weeks that (10) _____ only during periods of rain.

(6) _____

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.

Are you interested in seeing the beautiful fall foliage of New England but tired of traffic jams and overbooked hotels? Then this year forget the crowds in New England and see the beautiful colors of autumn in the Catskills.

These rugged mountains in New York State, just 90 miles northwest of New York City, are famous for the legendary tales of Rip Van Winkle, and more recently for the summer hotels that sprang up in the region during the 1940s, 1950s, and 1960s. Families trying to escape the heat of New York City found the Catskills to be the perfect place to stay for a month or so each summer. By the late 1950s there were over 500 resorts and hotels offering nighttime entertainment as well as all kinds of outdoor activities. Famous comedians like Jackie Gleason, Joan Rivers, and Sid Caesar all got their start touring the hotel clubs here. Since the introduction of air-conditioning and cheaper air travel, however, families have stopped coming to the Catskills in such large numbers, choosing instead more distant locations at different times of the year. Many of the Catskill hotels closed in the 1970s, but some remain and have expanded and changed their facilities to meet the needs of today's visitors.

Currently, there are many activities available to the traveler besides witnessing the changing colors of the leaves. There is an all-organic sheep farm where visitors can see how a traditional sheep farm operates. There are also hundreds of miles of scenic drives in the area. Route 42, for instance, is an excellent site for spotting bald eagles. For more information on vacations in the Catskills, call the Office of Public Information.

What is the author's main purpose in this passage?

Read the passage and choose the best answers to questions below. Write the answers on your answer sheet.

Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected.

The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.

On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree.

What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about.

As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too often
7.The word "potentially" in the passage most closely means_________ .

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.

   It is commonly believed in the United States that school is where people go to get an education. Nevertheless, it has been said that today children interrupt their education to go to school. The distinction between schooling and education implied by this remark is important.

   Education is much more open-ended and all-inclusive than schooling. Education knows no bounds. It can take place anywhere, whether in the shower or on the job, whether in a kitchen or on a tractor. It includes both the formal learning that takes place in schools and the whole universe of informal learning. The agents of education can range from a revered grandparent to the people debating politics on the radio, from a child to a distinguished scientist. Whereas schooling has a certain predictability, education quite often produces surprises. A chance conversation with a stranger may lead a person to discover how little is known of other religions. People are engaged in education from infancy on. Education, then, is a very broad, inclusive term. It is a lifelong process, a process that starts long before the start of school, and one that should be an integral part of one's entire life.

   Schooling, on the other hand, is a specific, formalized process, whose general pattern varies little from one setting to the next. Throughout a country, children arrive at school at approximately the same time, take assigned seats, are taught by an adult, use similar textbooks, do homework, take exams, and so on. The slices of reality that are to be learned, whether they are the alphabet or an understanding of the workings of government, have usually been limited by the boundaries of the subject being taught.

   For example, high school students know that they are not likely to find out in their classes the truth about political problems in their communities or what the newest filmmakers are experimenting with. There are definite conditions surrounding the formalized process of schooling.

The word “ integral” in line 13 is closest in meaning to

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions:
    In the Native American Navajo nation which sprawls across four states in the American south-west, the native language is dying. Most of its speakers are middle-age or elderly. Although many students take classes in Navajo, the schools are run in English. Street sign, supermarket goods and even their own newspaper are all in English. Not surprisingly, linguists doubt that any native speakers of Navajo will remain in a hundred years' time.
    Navajo is far from alone. Half the world's 6,800 languages are likely to vanish within two generations - that's one language lost every ten days. Never before has the planet's linguistic diversity shrunk at such a pace. Isolation breeds linguistic diversity as a result, the world is peppered with languages spoken by only a few people. Only 250 languages have more than a million speakers, and at least 3,000 have fewer than 2,500. It is not necessarily these small languages that are about to disappear. Navajo is considered endangered despite having 150,000 speakers. What makes a language endangered is not that the number of speakers, but how old they are. If it is spoken by children it is relatively safe. The critically endangered languages are those that are only spoken by the elderly, according to Michael Krauss, director of the Alaska Native Language Center, in Fairbanks.
    Why do people reject the language of their parent? It begins with a crisis of confidence, when a small community finds itself alongside a larger, wealthier society, says Nicholas Ostler of Britain's Foundation for Endangered Languages, in Bath. “People lose faith in their culture” he says. "When the next generation reaches their teens, they might not want to be induced into the old tradition.” The change is not always voluntary. Quite often, governments try to kill off a minority language by banning its use in public or discouraging its use in school, all to promote national unity. The former US policy of running Indian reservation in English, for example, effectively put languages such as Navajo on the danger list. But Salikoko Mufwene, who chairs the Linguistics Department at the University of Chicago, argues that the deadliest weapon is not government policy but economic globalisation. "Native Americans have not lost pride in their language, but they have had to adapt to socio-economic pressures" he says. “They cannot refuse to speak English if most commercial activity is in English."
    However, a growing interest in cultural identity may prevent the direct predictions from coming true. ‘The key to fostering diversity is for people to learn their ancestral tongue, as well as the dominant language' says Doug Whalen, founder and president of the Endangered Language Fund in New Haven, Connecticut. “Most of these will live without a large degree of bilingualism” he says.

It is stated in the passage that the number of endangered languages is ____.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blank from 36 to 40 .
Child workers, some as young as 10, have been found working in a textile factory in conditions described as close to slavery to produce clothes that appear destined for one of the major high street retailers.
The discovery of these children working in appalling conditions in the Shahpur Jat area of Delhi has renewed concerns about the (36)_______ by some large retail chains of their garment production to India, recognised (37)_______ the United Nations as one of the world‟s hotspots for child labour. According to one (38)_______ , over 20 percent of India's economy is dependent on children, (39)_______ comes to a total of 55 million youngsters under 14 working. Consumers in the West should not only be demanding answers from retailers about how their (40)_______ are produced but also should be looking  into their consciences at how they spend their money and whether cheap prices in the West are worth the suffering caused to so many children.
(38)..................

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

"The Southwestern States of the United States suffered one of the worst droughts in their history from 1931 to 1938. The drought (1)…. the entire country. Few food crops could be grown. Food became (2)…., and prices went up (3)….  the nation. Hundreds of families in the Dust Bowl region had to be moved to farms in other areas with the help of the federal government. In 1944, drought brought great damage to (4)…. all Latin America. The drought moved to Australia and then to Europe, (5)…. it continued throughout the summer of 1945. From 1950 to 1954 in the United States, the Southwest suffered a (6)….. drought Hundreds of cattle ranches had to ship their cattle to other regions because (7)… lands had no grass. The federal government again (8)….. an emergency drought-relief program. Ít offered farmers (9)…. credit and seed grains (10)… low prices."

6. From 1950 to 1954 in the United States, the Southwest suffered a (6)….. drought Hundreds of cattle ranches had to ship their cattle to other regions

Read the following passage and choose the correct answer in each sentence.

Last week, I had an occasion to — 131 — with Mr. Harries and Mr. Grava from your customer support team. I came to the office with a series of questions for a research project that I am working on. The information I needed tumed out to be more — 132— than I had anticipated but for awhile, your team was very patient, courteous and professional. — 133 —. It is clear that your customer service is one of the keys to your company’s success. I want you to know how much I — 134 — the assistance.

134...............

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.
There are many theories of aging, but virtually all fall into the category of hypotheses with a minimum of supporting evidence. One viewpoint is that aging occurs as the body's organ systems become less efficient. Thus failures in the immune system, hormonal system, and nervous system could all produce characteristics that we associate with aging. Following a different vein, many current researchers are looking for evidence at the cellular and sub cellular level. It has been shown that cells such as human fibroblasts (generalized tissue cells) grown in culture divide only a limited number of times and then die. Only cancer cells seem immortal in this respect. Fibroblast cells from an embryo divide more times than those taken from an adult. Thus some researchers believe that aging occurs at the cellular level and is part of the cell's genetic makeup. Any event that disturbs the cell's genetic machinery such as mutation, damaging chemicals in the cell's environment, or loss of genetic material, could cause cells to lose their ability to divide and thus bring on aging. Other theories of aging look at different processes. 
Chronological aging refers to the passage of time since birth and is usually measured in years. While chronological age can be useful in estimating the average status of a large group of people, it is a poor indicator of an individual person's status because there is a tremendous amount of variation from one individual to the next in regard to the rate at which biological age changes occur. For example, on the average, aging results in people losing much of their ability to perform strenuous activities, yet some elderly individuals are excellent marathon runners.
Another type of aging is cosmetic aging, which consists of changes in outward appearance with advancing age. This includes changes in the body and changes in other aspects of a person's appearance, such as the style of hair and clothing, the type of eyeglasses, and the use of a hearing aid. Like chronological aging, it is frequently used to estimate the degree to which other types of aging have occurred. However, it is an inaccurate indicator for either purpose because of variation among individuals and because a person's appearance is affected by many factors that are not part of aging, including illness, poor nutrition, and exposure to sunlight.

This article can be extracted from ______ .

Choose the item among A, B, C or D that best answers the question about the passage:

"The deserts of the world are not all covered with sand. Many of them have surfaces of rock or clay or small stones. They are not flat, either; they often have high hills and deep valleys. There is some plant life in many parts of the desert. There is little rain in the desert, but it does fall often enough for most plants. The deserts of the world are not uninhabited. People also live outside oases, but these people are not farmers. They have camels, goats, donkeys, sheep, etc. These animals can live on the desert plants and do not need much water.
 The people of the desert have to move constantly from place to place, they must always look for grass or desert plants for their animals. They usually live in tents. When there is no more food for their animals, they fold up their tents, put them on their camels and donkeys, and move to another place. In good years, when there is enough food for their animals, they trade their skins and their goats and camel hairs with the people of oases for wheat and fruit. But in bad years, when there is not enough food for their animals, the people of the desert would attack the oases people. But they are also hospitable. No man in the desert would ever refuse to give a stranger food and water."

5. From the passage we know that life ….

Choose the word (A, B, C, or D) that best fits each of the blank spaces.

Life after high school doesn't end. In fact, life begins once there are no more lockers, gym class, or teachers nagging you about homework.

In terms of choosing the (1) ____ career, it is important to consider a career assessment test in which you answer a series of questions designed to (2) ____ your strengths and weaknesses. While career tests should not be your main source of decision making, you can use them as a tool to help you decide what career might match your (3) ____.

Think about your interests and hobbies. If you enjoy science, you may want to apply to college and pursue a career in engineering or marine (4) ____.Write a list of possible careers that match your interests and your capabilities. If you find you are happiest when you work with others, jot down that you are a team player. In that case, you may want to consider jobs that involve people interaction instead of careers like computer programming or writing, which require more alone time. Speak to an adult you trust about your ideas and be willing to receive (5) ____.

Narrow your options and look for a career with growth (6) ____. While it is important to pick a career that will stimulate your mind, it is also important to be practical about the market. If you decide that you want to go to college, you will need to pick a career that enables you to make a living (7) ____ you graduate.

Jump into the first step of realizing your career dreams. If you have decided that you would like to pursue a career that requires higher education, do your (8) ____ on applying to the college or programme, including qualifications, application deadlines, tuition fees and length of study. If you have decided on a career that does not require higher education, start looking for ways to enter the field and (9) ____ experience. Speak to someone who already has your dream job. This person can provide a better picture of the pros and cons of the (10) ____

(4) ____

Choose the item among A, B, C or D thai best answers the question about the passage:

"Desert is the term applied to regions of the earth that are characterized by less than 254 mm (10. inches) of annual rainfall, an evaporation rate that exceeds precipitation, and, in most cases, a high average temperature. Because of a lack of moisture in the soil and low humidity in the atmosphere, most of the sunlight penetrates to the ground. Daytime temperatures can reach 55° c (131° F) in the shade. At night the desert floor radiates heat back to the atmosphere, and the temperature can drop to near freezing. Deserts are caused by a combination of climate patterns and geological features.
 Because so little water moves through the desert soil to carry nutrients away, desert soils are naturally fertile. Crops are grown on desert lands with water provided by irrigation from rivers or wells. Such transformations of deserts are not without problems. Evaporation of the irrigation water results in the accumulation of salt on the surface soil, eventually rendering it useless for further crop production. By tapping reservoirs of fossil water deep beneath the desert, humans are, in effect, mining water. Once this water is gone, it is irreplaceable. Burning and overgrazing of semiarid lands on the periphery of deserts can irreversibly damage the plants that concentrate moisture and hold the soil together, thus enabling deserts to encroach on arable land. This encroachment, a serious world problem, is called desertification. A 1984 report of a desertification study made for the United Nations stated that 35 percent of the earth’s land surface was at least threatened by such processes."

2. At night the temperature on deserts can drop to near freezing because

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. 
If you’ve done any traveling at all, you’re likely quite aware that customs and etiquette differ from one culture to another: what may be perfectly innocuous in one place may be hideously offensive in another, and vice-versa. Granted, even if you haven’t traveled at all, you’re probably aware of the fact that certain types of behavior aren’t exactly acceptable in other countries: belching at the table may be a sign of gratitude in some places, but in most areas of North America and Europe, such a display will earn you a fair bit of ire. Whether you plan on traveling to any of the places listed below or just doing business with a foreign client, it’s important to educate yourself on the standards of politesse and etiquette beforehand—the last thing you want to do is offend someone with any ignorant, boorish behavior. Here’s how to be polite in different countries.
When dealing with Japanese clients, be sure to dress fairly conservatively, and make sure that you bow lower than they do upon meeting them. Accept gifts with both hands and open them later, not in front of the giver, and never blow your nose at the dining table. Avoid asking and answering direct questions: it’s better to imply rather than ask, and to answer with vagueness during conversations.
In Mexico, when meeting others, women should initiate handshakes with men, but all people should avoid making too much eye contact; that can be seen as aggressive and belligerent behavior. If sharing a meal with others, keep your elbows off the table and try to avoid burping at all costs. Keep your hands off your hips, and make sure you never make the “okay” sign with your hand: it’s vulgar.
In Kenya, when greeting someone older or of a higher status than yourself, grip their right wrist with your left hand while shaking it; it’s a sign of respect and deference. Do ask questions about their health, family, business etc. before getting to major topics, as skipping these niceties is seen as impolite. If sharing meals, do not begin eating until the eldest male has been served and starts to eat.
Turning down an alcoholic drink is considered terribly offensive in Russia, so it’s a good idea to fortify yourself with some greasy food before heading out for a meal with Russian or Ukrainian clients. Don’t smile at strangers or they’ll think you’re deranged, and when paying for items, place your money on the counter rather than trying to hand it directly to the cashier.

According to the passage, which of the following behavior should be avoided when sharing meals with others?

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.

   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.

The “labellum” (line 7) is most comparable to

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks. 
        The "greenhouse effect" is the warming that happens when certain gases in Earth's atmosphere (23) ________ heat. These gases let in light but keep heat from escaping, like the glass walls of a greenhouse. First, sunlight shines onto the Earth's surface, (24) ______ it is absorbed and then radiates back into the atmosphere as heat. In the atmosphere, “greenhouse gases trap some of this heat, and the (25) ________ escapes into space. The more greenhouse gases are in the atmosphere, the more heat gets trapped. 
        Scientists have known about the greenhouse effect since 1824, when Joseph Fourier calculated that the Earth would be much colder if it had no atmosphere. This greenhouse effect is what keeps the Earth's climate (26) _________. Without it, the Earth's surface would be an average of about 60 degrees Fahrenheit cooler. Scientists often use the term "climate change" instead of global warming. This is because as the Earth's average temperature climbs, winds and ocean currents move heat around the globe in ways that can cool some areas, warm others, and change the amount of rain and snow falling. (27)_________, the climate changes differently in different areas.

First, sunlight shines onto the Earth's surface, (24) ______ it is absorbed and then radiates....

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.

        The "greenhouse effect" is the warming that happens when certain gases in Earth's atmosphere (23) ________ heat. These gases let in light but keep heat from escaping, like the glass walls of a greenhouse. First, sunlight shines onto the Earth's surface, (24) ______ it is absorbed and then radiates back into the atmosphere as heat. In the atmosphere, “greenhouse gases trap some of this heat, and the (25) ________ escapes into space. The more greenhouse gases are in the atmosphere, the more heat gets trapped.

        Scientists have known about the greenhouse effect since 1824, when Joseph Fourier calculated that the Earth would be much colder if it had no atmosphere. This greenhouse effect is what keeps the Earth's climate (26) _________. Without it, the Earth's surface would be an average of about 60 degrees Fahrenheit cooler. Scientists often use the term "climate change" instead of global warming. This is because as the Earth's average temperature climbs, winds and ocean currents move heat around the globe in ways that can cool some areas, warm others, and change the amount of rain and snow falling. (27)_________, the climate changes differently in different areas.

The "greenhouse effect" is the warming that happens when certain gases in Earth's atmosphere (23) ________ heat