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THE THREAT TO THE ENVIRONMENT

Nowadays people are more aware that wildlife all over the world is in danger. Many (1)________of animals are threatened, and could easily become (2)______ if we do not make an effort to protect them. There are many (3)_______ for this. In some cases, animals are hunted for their fur or for othervaluable parts of their bodies. Some birds, such as parrots, are caught (4)________and sold as pets. For many animals and birds, the problem is that their habitat - the (5)________where they live - is disappearing. More (6)________is used for farms, for houses or industry, and there are fewer open (7)________than there once were. Farmers use powerful chemicals to help them grow better (8)________, but these chemicals pollute the environment and (9)________wildlife. The most successful animals on earth - human beings - will soon be the only Ones left, unless we can (10)________this problem.

(5)________

Choose the letter A, B, C or D to complete the passage below

An endangered species is an animal or plant that's considered at …..(1)… of extinction. A species can be listed as endangered at the state, federal, and international level. On the federal level, the endangered species list is managed …..(2)…. the Endangered Species Act.

The Endangered Species Act (ESA) was ….. (3)…. by Congress in 1973. Under the ESA, the federal government has the responsibility to protect endangered species (species that are likely to become extinct throughout all or a large portion of their range), threatened species (species that are likely to become endangered in the near future), and critical habitat (areas vital to the survival of endangered or threatened species).

The Endangered Species Act has lists of protected plant and animal species….(4)….. nationally and worldwide. When a species is given ESA protection, it is said to be a "listed" species. Many additional species are evaluated for possible protection under the ESA, and they …..(5)…called “candidate” species.

(5) ..............

Overpopulation, the situation of having large numbers of people with too few resources and too little space, is closely associated with poverty. It can result from high population density, or from low amounts of resources, or from both. Excessively high population densities put stress on available resources. Only a certain number of people can be supported o a given area of land, and that number depends on how much food and other resources the land can provide. In countries where people live primarily by means of simple farming, gardening, herding, hunting, and gathering, even large areas of land can support only small numbers of people because these labor - intensive subsistence activities produce only small amounts of food.
In developed countries such as the United States, Japan and the countries of Western Europe, overpopulation generally is not considered a major cause of poverty. These countries produce large quantities of food through mechanized farming, which depends on commercial fertilizers, large - scale irrigation, and agricultural machinery. This form of production provides enough food to support the high densities of people in metropolitan areas.
A country's level of poverty can depend greatly on its mix of population density and agricultural productivity. Bangladesh, for example, has one of the world's highest population densities, with 1,147 persons per sq km. A large majority of the people of Bangladesh engage in low - productivity manual farming, which contributes to the country's extremely high level of poverty. Some of the smaller countries in Western Europe, such as the Netherlands and Belgium, have high population densities as well. These countries practice mechanized farming and are involved in high - tech indutries, however, are therefore have high standards of living.
At the other end of the spectrum, many countries in sub - Saharan Africa have population densities of less than 30 persons per sq km. Many people in these countries practice manual subsistence farming, these countries also have infertile land, and lack the economic resources and technology to boost productivity. As a consequence, these nations are very poor. The United States has both relatively low population density and high agricultural productivity; it is one of the world's weathiest nations.
High birth rates contribute to overpopulation in many developing countries. Children are assets to many poor families because they provide labor, usually for farming. Cultural norms in traditionally rural societies commonly sanction the value of large families. Also, the goverments of developing countries often provide little or no support, financial or political, for farming planning; even people who wish to keep their families small have difficulty doing so. For all those reasons, developing countries tend to have high rates of population growth.

What will suffer when there are excessively high population densities?

Choose the best answer:
After more than fifty years of television, it might seem only obvious to conclude that it is here to (1) ______ . There have been many objections to it during this time, of course, and (2) ______ a variety of grounds. Did it cause eye-strain? Was the (3) ______ bombarding us with radioactivity? Did the advertisements contain subliminal messages, persuading us to buy more? Did children turn to violence through watching it, either because so (4) ______ programmes taught them how to shoot, rob, and kill, or because they had to do something to counteract the hours they had spent glued to the tiny screen? Or did it simply create a vast passive (5) ______ drugged by glamorous serials and inane situation (6) ______ ? On the other hand did it increase anxiety by sensationalizing the news [or the news which was (7) ______ by suitable pictures] and filling our living rooms with war, famine and political unrest? (8) ______ in all, television proved to be the all-purpose scapegoat for the second half of the century, blamed for everything, but above all, eagerly watched. For no (9) ______ how much we despised it, feared it, were bored by it, or felt that it took us away from the old paradise of family conversation and hobbies such as collecting stamps, we never turned it off. We kept staring at the screen, aware that our own tiny (10) ______ was in if we looked carefully.
2.

Choose the best answer to complete the passage.

LEARNING HOW TO LEARN AND THINK

What is the point of the education system? Although this question may seem ridiculous at first (1) ____, it is actually not stupid as it sounds. The reason it is (2) ____ trying to answer is that schools and university clearly (3) ____ academic achievement, passing exams and gaining (4) ____ much more than acquiring skills such as (5) ____ children or car maintenance. But why is it? Why do they neglect to teach (6) ____ skills at school?

One answer may be that schools don't (7) ____ to help us gain useful knowledge about the world. At school, what we are (8) ____ learning is how to learn effectively. The idea is that we can then (9) ____ use of that ability later on in life when we come to deal (10) ____ more practical aspects of day- to-day living.

However, some people argue that the (11) ____ system is in fact a failure because it doesn't actually teach children how to become good thinkers. Learning how to learn is one thing. Learning how to learn is one thing. Learning how to think is (12) ____ another.

(10) ____

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. 
       A little while ago, the European Parliament recommended a list of 8 key competencies which they believe all (23) ____ institutions should provide their students with, to promote lifelong learning. These key competencies consist of knowledge, skills, and attitudes which are central to the development of (24) ____ children, young people and eventually adults.
       Finland isn't the first country to recognize the value of ‘lifelong learning’ but Finland is the first country to base their teaching curriculum (25) ____ the eight key competencies. Instead of focusing on classic academic subjects, like. History or English, Finnish schools will now structure lessons around broader, crosscutting and interdisciplinary "topics".
       Speaking on why Finland decided to make this shift towards lifelong learning. Pasi Sahlberg. Visiting Professor at the Graduate School of Education Harvard University, said: “educators in Finland think, quite correctly, that schools should teach what young people need in their lives... (26) ______Finnish youth need more than before are more integrated knowledge and skills about real world issues”.
       As Professor Sahlberg explains the key competencies don't focus on knowledge acquisition and test score results, (27) ____ on developing skills for longer term learning, with an emphasis on social and emotional development.

 Finland isn't the first country to recognize the value of ‘lifelong learning’ but Finland is the first country to base their teaching curriculum (25) ____ the eight key competencies.

Choose the letter A, B, C or D to answer these following questions:
   Dinosaurs were reptiles that lived during a period of earth’s history called the Mesozoic Era, which is also known as the Age of Reptiles. The first dinosaurs appeared more than 200 million years ago. For many millions of years, they dominated the land with their huge size and strength. Then about 65 million years ago, they died out rather suddenly, never to re-emerge. The word “dinosauras” comes from two Greek words meaning “terrible lizard”. Dinosaurs were not lizards, but their appearance could be truly terrifying. The biggest ones weighed more than ten times as much as a mature elephant and nearly equalled the size of most modern-day whales. The famous kinds of dinosaurs, including the brontosaur and tyrannosaurus rex, reached 80 to 90 feet in length. Not all dinosaurs were giant, however, some were actually not larger than a chicken. Scientists still do not know what caused dinosaurs to disappear. One theory involves a change of the earth’s climate. It is believed that temperatures dropped significantly towards the end of the Cretaceous protection, it is possible that the climate became too chilly for dinosaurs. In contrast, other species having protection, such as the mammals and birds, were able to survive.

The author uses the phrase "never to re-emerge" to indicate that the dinosaurs_____.

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

The World Wide Fund for Nature (WWF) is an international (26) _____- governmental organization for the (27) _____, research, and restoration of the environment. The organization was (28) _____ as a charitable trust on September 11, 1961, in Morges, Switzerland, under the name World Wildlife Fund. It was an initiative of Julian Huxley and Max Nicholson.It is the world's largest independent conservation organization with over 5 million (29) _____ worldwide, working in more (30) _____ 90 countries, supporting 100 conservation and environmental projects around the world. It is a charity, with (31) ____ 9% of its funding coming from voluntary (32) ___ by private individuals and businesses.The group says its mission is "to halt and reverse the (33) _____ of our environment". Currently, much of its work focuses on the conservation of three biomes that contain most of the world's biodiversity: forests, freshwater ecosystems, and oceans and coasts. Among other issues, it is also concerned (34) _____ endangered species, pollution, and climate change. The organization (35) ____ more than 20 field projects worldwide. In the last few years, the organization set up offices and operations around the world.

(32) _____

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 was a man who had four sons. He wanted his sons to learn not to judge things too quickly. So he sent them each on a quest, in turn, to go and look at a pear tree that was a great distance away. The first son went in the winter, the second in the spring, the third in summer, and the youngest son in the fall. When they had all gone and come back, he called them together to describe what they had seen.
The first son said that the tree was ugly, bent, and twisted. The second son said no – it was covered with green buds and full of promise. The third son disagreed, he said it was laden with blossoms that smelled so sweet and looked so beautiful, it was the most graceful thing he had ever seen. The last son disagreed with all of them; he said it was ripe and drooping with fruit, full of life and fulfilment.
The man then explained to his sons that they were all right, because they had each seen but one season in the tree’s life. He told them that you cannot judge a tree, or a person, by only one season, and that the essence of who they are – and the pleasure, joy, and love that come from that life – can only be measured at the end, when all the seasons are up. If you give up when it’s winter, you will miss the promise of your spring, the beauty of your summer, fulfilment of your fall.
Don’t judge a life by one difficult season. Don’t let the pain of one season destroy the joy of all the rest.

The word “they” in paragraph 3 refers 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. 
     How might volunteering contribute to lower blood pressure? Performing volunteer work could increase physical activity among people who aren’t otherwise very active, says lead study author Rodlescia Sneed, a doctoral candidate in social and health psychology at Carnegie Mellon University. It may also reduce stress. “Many people find volunteer work to be helpful with respect to stress reduction, and we know that stress is very strongly linked to health outcomes,” she says.
     As with any activity thought to improve health, researchers are trying to identify the specific characteristics of volunteering that provide the greatest benefit. For example, how much time would you need to put into volunteer work to lower your blood pressure or live longer? In the Carnegie Mellon study, 200 hours of volunteering per year correlated to lower blood pressure. Other studies have found a health benefit from as little as 100 hours of volunteering a year. Which types of volunteer activities improve health the most? No one really knows. Sneed speculates that mentally stimulating activities, like tutoring or reading, might be helpful for maintaining memory and thinking skills, while “activities that promote physical activity would be helpful with respect to cardiovascular health, but no studies have really explored this.”
     One key for deriving health benefits from volunteering is to do it for the right reasons. A 2012 study in the journal Health Psychology found that participants who volunteered with some regularity lived longer, but only if their intentions were truly altruistic. In other words, they had to be volunteering to help others—not to make themselves feel better.
      The Greek philosopher Aristotle once surmised that the essence of life is “To serve others and do good.” If recent research is any indication, serving others might also be the essence of good health.

According to paragraph 4, what is the lesson from one of the greatest intellectual figures in history?

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

"Do you want to take part in the battle to save the world’s wildlife? “Animal Watch” is a book which will (1)….. you in the fight for survival that (2)….  many of our endangered animals and show how they struggle on the (3)…. of extinction. As you enjoy the book’s 250 pages and over 150 coloured photographs, you will have the (4)…..  of knowing that part of your purchase money is being used to help animals (5)…. . From the comfort of your armchair, you will be able to observe the world’s animals close-up and explore their habitats. You will aỉso discover the terrible results of human greed for land, flesh and skins.
 “Animal Watch” is packed with fascinating facts. Did you know that polar bears cover their black noses (6)…. their paws so they can hunt their prey in the snow without being seen, for example? Or that for each orangutan which is captured, one has to die?
 This superb (7)…. has so (8)….. Britain’s leading wildlife charity that it has been chosen as Book of the Year, a (9)….. awarded to books which are considered to have made a major contribution to wildlife conservation. You will find “Animal Watch” at a special low introductory at all good bookshops, but hurry while (10)….. last."

2. that (2)….  many of our endangered animals

Choose the letter A, B, C or D to answer these following questions:
Alligators have always been the most dangerous predators of the Florida Everglades, but their long-held position is now being challenged by a growing population of Burmese pythons.
The Burmese python, a giant snake measuring up to 20 feet long and weighing up to 200 pounds, is very popular among exotic pet owners. However, as the dead snakes grow, they become more difficult to cage and handle. To avoid dealing with the snakes, the owners irresponsibly release them into the wild. Since the Everglades is quietly similar to the python's native environment of Southeast Asia, they survive and prosper without difficulty.
The issue with the Burmese pythons is their choice of meals. They eat alligators and endangered birds, which creates strain on an already fragile ecosystem. Recently a 13-foot long Burmese python was found with a 5-foot alligator bursting from its stomach. The python died tried to eat the alligator but a larger one would have easily won the struggle. With over 30,000 Burmese pythons now living over the Everglades, a solution to stop this invasive species is necessary. If the pythons are left unchecked, there is a strong possibility they will wipe out a variety of species needed for the functioning of the Everglades ecosystem.

Why do Burmese pythons develop and prosper in a simple and easy way?

Choose the letter A, B, C or D to answer these following questions

   In developing countries, people are sometimes unaware of the importance of education, and there is economic pressure from those parents who prioritize their children's, making money in the short term over any long-term benefits of education. Recent studies on child labor and, poverty have suggested that when poor families reach a certain economic threshold where families are able to provide for their basic needs, parents return their children to school. This has been found to be true, once the threshold has been breached, even if the potential economic value of the children's work has increased since their return to school. Other problems are that teachers are often paid less than other professions; a lack of good universities and a low acceptance rate for good universities are evident in countries with a relatively high population density. India has launched EDUSAT, an education satellite that can reach remote parts of the country at a greatly reduced cost. There is also ail initiative supported by several major corporations to develop a $100 laptop. The laptops have been available since 2007. The laptops, sold at cost, will enable developing countries to give their children a digital education. In Africa, an "e-school program" has been launched to provide all 600,000 primary and high schools with computer equipment, learning materials and internet access within 10 years. Volunteer groups are working to give more individuals opportunity to receive education in developing countries through such programs as the Perpetual Education Fund. An International Development Agency project started with the support of American President Bill Clinton uses the Internet to allow co-operation by individuals on issues of social development.

In developing countries, ________.

Read the following passage and choose among A, B, C or D the correct answer to each of the questions.

In my experience, freshmen today are different from those I knew when I started as a counselor and professor 25 years ago. College has always been demanding both academically and socially. But students now are less mature and often not ready for the responsibility of being in college.

It is really too easy to point the finger at parents who protect their children from life's obstacle. Parents, who handle every difficulty and every other responsibility for their children writing admission essays to picking college courses, certainly may contribute to their children's lack of coping strategies. But we can look even more broadly to the social trends of today.

How many people do you know who are on medication to prevent anxiety or depression? The number of students who arrive at college already medicated for unwanted emotions has increased dramatically in the past 10 years. We, as a society, don't want to "feel" anything unpleasant and we certainly don't want our children to "suffer".

The resulting problem is that by not experiencing negative emotions, one does not learn the necessary skills to tolerate and negotiate adversity. As a psychologist, I am well aware of the fact that some individuals suffer from depression and anxiety and can benefit from treatment, but I question the growing number of medicated adolescents today.

Our world is more stressful in general because of the current economic and political realities, but I don't believe that the college experience itself is more intense today than that of the past 10 years. What I do think is that many students are often not prepared to be young "adults" with all the responsibilities of life.

What does this mean for college faculty and staff? We are required to assist in the basic parenting of these students - the student who complains that the professor didn't remind her of the due date for an assignment that was clearly listed on the syllabus and the student who cheats on an assignment in spite of careful instructions about plagiarism.

As college professors, we have to explain what it means to be an independent college student before we can even begin to teach. As parents and teachers we should expect young people to meet challenges. To encourage them in this direction, we have to step back and let them fail and pick themselves up and move forward. This approach needs to begin at an early age so that college can actually be a passage to independent adulthood.

The phrase "on medication" in paragraph 3 is similar in meaning to ____.

Reading to oneself is a modern activity which was almost unknown to the scholars of the classical and medieval worlds, while during the fifteenth century the term "reading" undoubtedly meant reading aloud. Only during thenineleenthcenturydid silent reading become commonplace.
One should be wary, however, of assuming that silent reading came about simply because reading aloud was a distraction to others. Examinations of factors related to the historical development of silent reading have revealed that it became the usual mode  of reading for most adults mainly because the tasks themselves changed in character.
The last century saw a steady gradual increase in literacy and thus in the number of readers. As the number of readers increased, the number of potential listeners declined and thus there was some reduction in the need to read aloud. As reading for the benefit of listeners grew less common, so came the flourishing of reading as a private activity in such public places as libraries, railway carriages and offices, where reading aloud would cause distraction to other readers.
Towards the end of the century, there was still considerable argument over whether books should be used for information or treated respectfully and over whether the reading of  materials such as newspapers was in some way mentally weakening. Indeed, this argument remains with us still in education. However, whatever its virtues, the old shared literacy  culture had gone and was replaced by the printed mass media on the one hand and by books and periodicals for a specialised readership on the other.
By the end of the twentieth century, students were being recommended to adopt attitudes to books and to use reading skills which were inappropriate, if not impossible, for the oral reader. The social, cultural and technological changes in the century had greatly altered what the term "reading" implied.

It can be inferred that the emergence of the mass media and specialised reading materials was an indication of .........................

It's often said that we learn things at the wrong time. University students frequently do the minimum of work because they're crazy about a good social life instead. Children often scream before their piano practice because it’s so boring. They have to be given gold stars and medals to be persuaded to swim, or have to be bribed to take exams. But the story is different when you’re older.
Over the years, I've done my share of adult learning. At 30, I went to a college and did courses in History and English. It was an amazing experience. For starters, I was paying, so there was no reason to be late - I was the one frowning and drumming my fingers if the tutor was late, not the other way round. Indeed, if I could persuade him to linger for an extra five minutes, it was a bonus, not a nuisance. I wasn't frightened to ask questions, and homework was a pleasure not a pain. When I passed an exam, I had passed it for me and me alone, not for my parents or my teachers. The satisfaction I got was entirely personal
Some people fear going back to school because they worry that their brains have got rusty. But the joy is that, although some parts have rusted up, your brain has learnt all kinds of other things since you were young. It has learnt to think independently and flexibly and is much better at relating one thing to another. What you lose in the rusty department, you gain in the maturity department.
In some ways, age is a positive plus. For instance, when you're older, you get less frustrated. Experience has told you that, if you're calm and simply do something carefully again and again, eventually you'll get the hang of it. The confidence you have in other areas - from being able to drive a car, perhaps - means that if you can’t, say, build a chair instantly, you don't, like a child, want to destroy your first pathetic attempts. Maturity tells you that you will, with application, eventually get there.
I hated piano lessons at school, but I was good at music. And coming back to it, with a teacher who could explain why certain exercises were useful and with musical concepts that, at the age of ten, I could never grasp, was magical. Initially, I did feel a bit strange, thumping out a piece that I'd played for my school exams, with just as little comprehension of what the composer intended as I'd had all those years before. But soon, complex emotions that I never knew poured out from my fingers, and suddenly I could understand why practice makes perfect.

It can be inferred from paragraph 4 that maturity is a positive plus in the learning process because adult learners   ...............

Choose the best answer:
After more than fifty years of television, it might seem only obvious to conclude that it is here to (1) ______ . There have been many objections to it during this time, of course, and (2) ______ a variety of grounds. Did it cause eye-strain? Was the (3) ______ bombarding us with radioactivity? Did the advertisements contain subliminal messages, persuading us to buy more? Did children turn to violence through watching it, either because so (4) ______ programmes taught them how to shoot, rob, and kill, or because they had to do something to counteract the hours they had spent glued to the tiny screen? Or did it simply create a vast passive (5) ______ drugged by glamorous serials and inane situation (6) ______ ? On the other hand did it increase anxiety by sensationalizing the news [or the news which was (7) ______ by suitable pictures] and filling our living rooms with war, famine and political unrest? (8) ______ in all, television proved to be the all-purpose scapegoat for the second half of the century, blamed for everything, but above all, eagerly watched. For no (9) ______ how much we despised it, feared it, were bored by it, or felt that it took us away from the old paradise of family conversation and hobbies such as collecting stamps, we never turned it off. We kept staring at the screen, aware that our own tiny (10) ______ was in if we looked carefully.
6.

Overpopulation, the situation of having large numbers of people with too few resources and too little space, is closely associated with poverty. It can result from high population density, or from low amounts of resources, or from both. Excessively high population densities put stress on available resources. Only a certain number of people can be supported o a given area of land, and that number depends on how much food and other resources the land can provide. In countries where people live primarily by means of simple farming, gardening, herding, hunting, and gathering, even large areas of land can support only small numbers of people because these labor - intensive subsistence activities produce only small amounts of food.
In developed countries such as the United States, Japan and the countries of Western Europe, overpopulation generally is not considered a major cause of poverty. These countries produce large quantities of food through mechanized farming, which depends on commercial fertilizers, large - scale irrigation, and agricultural machinery. This form of production provides enough food to support the high densities of people in metropolitan areas.
A country's level of poverty can depend greatly on its mix of population density and agricultural productivity. Bangladesh, for example, has one of the world's highest population densities, with 1,147 persons per sq km. A large majority of the people of Bangladesh engage in low - productivity manual farming, which contributes to the country's extremely high level of poverty. Some of the smaller countries in Western Europe, such as the Netherlands and Belgium, have high population densities as well. These countries practice mechanized farming and are involved in high - tech indutries, however, are therefore have high standards of living.
At the other end of the spectrum, many countries in sub - Saharan Africa have population densities of less than 30 persons per sq km. Many people in these countries practice manual subsistence farming, these countries also have infertile land, and lack the economic resources and technology to boost productivity. As a consequence, these nations are very poor. The United States has both relatively low population density and high agricultural productivity; it is one of the world's weathiest nations.
High birth rates contribute to overpopulation in many developing countries. Children are assets to many poor families because they provide labor, usually for farming. Cultural norms in traditionally rural societies commonly sanction the value of large families. Also, the goverments of developing countries often provide little or no support, financial or political, for farming planning; even people who wish to keep their families small have difficulty doing so. For all those reasons, developing countries tend to have high rates of population growth.

Which of the following could be the best title for the passage?

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.
Engineers have dreaming of an underwater link between Britain and France (35)_____1802. Finally in 1994 the Channel Tunnel ( nicknamed "The Chunnel" by the English) was (36)______ opened.
This fifteen billion dollar project took seven years to (37)_____. It is about 50 km long and built 45metres under the seabed .The trains which go through the Chunnel can travel at up 300 km/h due to the (38)_______electrical system.
The journey from London to Paris via the Chunnel takes just three hours. It is also (39)______ for drivers since they can load their cars onto the trains. They don't need to book in (40)______ , as trains (41)_______every few minutes. However, while on the train, there isn't much to do and many (42)_________ the Chunnel for this (43)________ the ferries , there is no duty-free shopping , no videogame parlou or refreshment stand (44)________can you look outside and enjoy the view . As a result, many would find the Chunnel unappealing and would take the ferry instead.
(38).......................................... 
 

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: 
We are descendents of the ice age. Periods of glaciation have spanned the whole of human existence for the past 2 million years. The rapid melting of the continental glaciers at the end of the last ice age spurred one of the most dramatic climate changes in the history of the planet. During this interglacial time, people were caught up in a cataclysm of human accomplishment, including the development of agriculture and animal husbandry. Over the past few thousand years, the Earth’s climate has been extraordinarily beneficial, and humans have prospered exceedingly well under a benign atmosphere. Ice ages have dramatically affected life on Earth almost from the very beginning. It is even possible that life itself significantly changed the climate. All living organisms pull carbon dioxide out of the atmosphere and eventually store it in sedimentary rocks within the Earth’s crust. If too much carbon dioxide is lost, too much heat escapes out into the atmosphere. This can cause the Earth to cool enough for glacial ice to spread across the land. In general the reduction of the level of carbon dioxide in the atmosphere has been equalized by the input of carbon dioxide from such events as volcanic eruptions. Man, however, is upsetting the equation by burning fossil fuels and destroying tropical rain forests, both of which release stored carbon dioxide. This energizes the greenhouse effect and causes the Earth to warm. If the warming is significant enough, the polar ice caps eventually melt. The polar ice caps drive the atmospheric and oceanic circulation systems. Should the ice caps melt, warm tropical waters could circle the globe and make this a very warm, inhospitable planet. Over the past century, the global sea level has apparently risen upwards of 6 inches, mainly because of the melting of glacial ice. If present warming trends continue, the seas could rise as much as 6 feet by the next century. This could flood coastal cities and fertile river deltas, where half the human population lives. Delicate wetlands, where many marine species breed, also would be reclaimed by the sea. In addition, more frequent and severe storms would batter coastal areas, adding to the disaster of the higher seas. The continued melting of the great ice sheets in polar regions could cause massive amounts of ice to crash into the ocean. This would further raise the sea level and release more ice, which could more than double the area of sea ice and increase correspondingly the amount of sunlight reflected back into space. The cycle would then be complete as this could cause global temperatures to drop enough to initiate another ice age.

What does the final paragraph of the passage mainly discuss?

Choose the best answer

No more polar bear?

We all know that the Earth is growing warmer and warmer. This problem is called “global warming”. We also know that global warming is causing a lot of problems. Ocean levels are getting higher and higher. Because ocean levels are getting higher, storms are getting stronger and stronger. This list of problems goes on and on.

Animals are suffering a lot because of global warming. Polar bears are suffering more than most animals. This is because polar bears live in the North Pole. In the North Pole, global warming is making ice melt. Polar bears hunt from large pieces of floating ice. They jump off the ice and hunt for food. Polar bears have to swim and find these floating pieces of ice. These days, they have to swim farther to find the floating ice. Many of them don’t have enough energy. They get too tired, and they die in the water.

Polar bears are suffering because of other problems, too. Pollution makes their water dirty. Many countries go to the North Pole to look for oil and gas, and they damage the environment of the bears. In addition, when ships sail through the North Pole, they cause a lot of damage. Finally, people hunt and kill too many polar bears. However, melting ice is definitely the biggest problem.

Right now, there are about 25,000 polar bears in the world. If global warming continues, there may be only about 12,000 in the year 2050. By the year 2080, that number might be much smaller.

It is important to study polar bears. When we learn about polar bears, we also learn about the health of the North Pole. If polar bears are doing well, then the environment in the North Pole is probably healthy. If polar bears are suffering then there are probably serious problems in the North Pole.

Right now, governments around the world are working to help polar bears. There are new laws that protect polar bears. However, if global warming continues to get worse, polar bears may disappear forever.

Which of the following is true according to the passage?