Unlike buried treasure and some minerals, fossils are usually not valuable in themselves. However, most of the fossils you find will be of greatest value to you. They will help you learn much about the geologic history of the earth and its inhabitants.

If it were not for fossils, we would have no way of knowing about the animals that once roamed the earth or that once crawled on the bottom of the ancient seas. In fact, we would not even know for sure that there were once seas in some regions if it were not for the many fossils of sea animals that we find there.

You can look at some fossils and see for yourself the shape of the ancient animals. Even if you collect only bits of one kind of fossil, you may still be able to tell what it looked like. Making sense out of fossil bits is a little like working a jigsaw puzzle. Sometimes you will lose pieces, but you can still recognize the picture and even use your imagination to fill in missing details. The habits of ancient sea animals are not so easy to determine. Therefore, scientists study the structure and the habits of similar living animals to learn what the ancient ones must have been like. There are some things, however, that neither the study of fossils nor the study of living animals can tell us. For example, no one knows what colour most ancient sea animals were. Also, since the soft parts disappeared soon after death, many details of their internal structure are unknown. So the pictures of ancient sea creatures (as well as dinosaurs!) are what scientists think the animals looked like. Reconstructing the life of an ancient sea animal on the basis of fossil evidence and the characteristics of similar living animals is a little like relying on circumstantial evidence in court.

1. This passage is mainly about animals that __________.

A. have very tough hides

B. once lived on the earth

C. inhabit the seas of today

D. are becoming extinct

2. With the help of fossils we can __________.

A. reconstruct life of the past

B. predict the future

C. explain the changes of the seasons

D. save some species of animals from extinction

3. Many details of ancient animals are lacking because __________.

A. many species have not been found

B. volcanic disasters have permanently buried many fossils

C.many fossils lie in deep water and cannot be recovered

D. soon after death the soft parts of the body decay

49. To “determine" in the passage is closest in meaning to __________.

A. come across

B. study

C. find out

D. imitate

50. This passage implies that a scientist's evaluation of the past is based on __________.

A. laboratory experiments with live animals

B. a few facts mixed with a lot of opinions

C. predictions made in the past and present

D. field studies of our society

Read the following passage, and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer for each of the blanks.

The future of the African elephant depends on man. No (31)_________ can human beings and wild animals live in harmony throughout vast area of the continent as was possible in days gone by, for man’s needs have increased as well as his numbers. There are regions, such as the Congo forests and the equatorial Sudan, (32)_________ the old relationship may remain for a few more years or even generations, but in general it has gone. Conservation, if it is to be effective, should be a positive, constructive policy, and it is wishful thinking to imagine otherwise, (33)_________ in the case of the elephant. And this is not yet true of the whole of Africa, it soon will be, for the increase in the human population is almost universal. Where human beings and wild animals find themselves in competition with each other, the animals will (34)_________ Even if there appears to be enough room for both, man will not tolerate long a situation in which elephants and other (35)_________ make even occasional raids on his fields of food or economic crops. For many years this has been a major cause of conflicting interests and one of the reasons why so many elephants have been shot to control their numbers

 Điền vào ô số 34

A. win 

B. lose

C. disappear 

D. fight

Read the following passage, and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer for each of the blanks.

The future of the African elephant depends on man. No (31)_________ can human beings and wild animals live in harmony throughout vast area of the continent as was possible in days gone by, for man’s needs have increased as well as his numbers. There are regions, such as the Congo forests and the equatorial Sudan, (32)_________ the old relationship may remain for a few more years or even generations, but in general it has gone. Conservation, if it is to be effective, should be a positive, constructive policy, and it is wishful thinking to imagine otherwise, (33)_________ in the case of the elephant. And this is not yet true of the whole of Africa, it soon will be, for the increase in the human population is almost universal. Where human beings and wild animals find themselves in competition with each other, the animals will (34)_________ Even if there appears to be enough room for both, man will not tolerate long a situation in which elephants and other (35)_________ make even occasional raids on his fields of food or economic crops. For many years this has been a major cause of conflicting interests and one of the reasons why so many elephants have been shot to control their numbers

 Điền vào ô số 32

A. where 

B. when 

C. how 

D. why

Read the following passage, and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer for each of the blanks.

The future of the African elephant depends on man. No (31)_________ can human beings and wild animals live in harmony throughout vast area of the continent as was possible in days gone by, for man’s needs have increased as well as his numbers. There are regions, such as the Congo forests and the equatorial Sudan, (32)_________ the old relationship may remain for a few more years or even generations, but in general it has gone. Conservation, if it is to be effective, should be a positive, constructive policy, and it is wishful thinking to imagine otherwise, (33)_________ in the case of the elephant. And this is not yet true of the whole of Africa, it soon will be, for the increase in the human population is almost universal. Where human beings and wild animals find themselves in competition with each other, the animals will (34)_________ Even if there appears to be enough room for both, man will not tolerate long a situation in which elephants and other (35)_________ make even occasional raids on his fields of food or economic crops. For many years this has been a major cause of conflicting interests and one of the reasons why so many elephants have been shot to control their numbers

 Điền vào ô số 35

A. people 

B. plants 

C. descendants 

D. creatures

Read the following passage, and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer for each of the blanks.

The future of the African elephant depends on man. No (31)_________ can human beings and wild animals live in harmony throughout vast area of the continent as was possible in days gone by, for man’s needs have increased as well as his numbers. There are regions, such as the Congo forests and the equatorial Sudan, (32)_________ the old relationship may remain for a few more years or even generations, but in general it has gone. Conservation, if it is to be effective, should be a positive, constructive policy, and it is wishful thinking to imagine otherwise, (33)_________ in the case of the elephant. And this is not yet true of the whole of Africa, it soon will be, for the increase in the human population is almost universal. Where human beings and wild animals find themselves in competition with each other, the animals will (34)_________ Even if there appears to be enough room for both, man will not tolerate long a situation in which elephants and other (35)_________ make even occasional raids on his fields of food or economic crops. For many years this has been a major cause of conflicting interests and one of the reasons why so many elephants have been shot to control their numbers

 Điền vào ô số 33

A. certainly 

B. particularly 

C. only 

D. entirely

Read the following passage, and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer for each of the blanks.

The future of the African elephant depends on man. No (31)_________ can human beings and wild animals live in harmony throughout vast area of the continent as was possible in days gone by, for man’s needs have increased as well as his numbers. There are regions, such as the Congo forests and the equatorial Sudan, (32)_________ the old relationship may remain for a few more years or even generations, but in general it has gone. Conservation, if it is to be effective, should be a positive, constructive policy, and it is wishful thinking to imagine otherwise, (33)_________ in the case of the elephant. And this is not yet true of the whole of Africa, it soon will be, for the increase in the human population is almost universal. Where human beings and wild animals find themselves in competition with each other, the animals will (34)_________ Even if there appears to be enough room for both, man will not tolerate long a situation in which elephants and other (35)_________ make even occasional raids on his fields of food or economic crops. For many years this has been a major cause of conflicting interests and one of the reasons why so many elephants have been shot to control their numbers

 Điền vào ô số 31.

A. more 

B. condition 

C. circumstance 

D. longer

Read the following passage and blacken the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

        Sharks have gained an unfair reputation for being fierce predators of large sea animals. Humanity's unfounded fear and hatred of these ancient creatures is leading to a worldwide slaughter that may result in the extinction of many coastal shark species. The shark is the victim of a warped attitude of wildlife protection; we strive only to protect the beautiful, non-threatening parts of our environment. And, in our efforts to restore only non-threatening parts of our earth, we ignore other important parts.

        A perfect illustration of this attitude is the contrasting attitude toward another large sea animal, the dolphin. During the 1980s, environmentalists in the United States protested the use of driftnets for tuna fishing in the Pacific Ocean since these nets also caught dolphins. The environmentalists generated enough political and economic pressure to prevent tuna companies from buying tuna that had been caught in driftnets. In contrast to this effort on behalf of the dolphins, these same environmentalists have done very little to help save the Pacific Ocean sharks whose population has decreased nearly to the point of extinction.

Sharks are among the oldest creatures on earth, having survived in the seas for more than 350 million years. They are extremely efficient animals, feeding on wounded or dying animals, thus performing an important role in nature of weeding out the weaker animals in a species. Just the fact that species such as the Great White Shark have managed to live in the oceans for so many millions of years is enough proof of their efficiency and adaptability to changing environments. It is time for US humans, who may not survive another 1,000 years at the rate we are damaging the planet, to cast away our fears and begin considering the protection of sharks as an important part of a program for protection of all our natural environment.

How did environmentalists manage to protect dolphins?

A. They prevented fishermen from selling them for meat.

B. They pressured fishermen into protecting dolphins by law.

C. They brought political pressure against tuna companies.

D. They created sanctuaries where dolphin fishing was not allowed.

Read the following passage and blacken the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

        Sharks have gained an unfair reputation for being fierce predators of large sea animals. Humanity's unfounded fear and hatred of these ancient creatures is leading to a worldwide slaughter that may result in the extinction of many coastal shark species. The shark is the victim of a warped attitude of wildlife protection; we strive only to protect the beautiful, non-threatening parts of our environment. And, in our efforts to restore only non-threatening parts of our earth, we ignore other important parts.

        A perfect illustration of this attitude is the contrasting attitude toward another large sea animal, the dolphin. During the 1980s, environmentalists in the United States protested the use of driftnets for tuna fishing in the Pacific Ocean since these nets also caught dolphins. The environmentalists generated enough political and economic pressure to prevent tuna companies from buying tuna that had been caught in driftnets. In contrast to this effort on behalf of the dolphins, these same environmentalists have done very little to help save the Pacific Ocean sharks whose population has decreased nearly to the point of extinction.

Sharks are among the oldest creatures on earth, having survived in the seas for more than 350 million years. They are extremely efficient animals, feeding on wounded or dying animals, thus performing an important role in nature of weeding out the weaker animals in a species. Just the fact that species such as the Great White Shark have managed to live in the oceans for so many millions of years is enough proof of their efficiency and adaptability to changing environments. It is time for US humans, who may not survive another 1,000 years at the rate we are damaging the planet, to cast away our fears and begin considering the protection of sharks as an important part of a program for protection of all our natural environment.

How did environmentalists manage to protect dolphins?

A. They prevented fishermen from selling them for meat.

B. They pressured fishermen into protecting dolphins by law.

C. They brought political pressure against tuna companies.

D. They created sanctuaries where dolphin fishing was not allowed.

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions.

The Amazon rainforest is home to more than a third of all the world's species of plants, birds and animals. Twenty per cent of all the birds in the world live in the rainforest. Scientists have discovered thousands of types of plants and animals that can only be found there. There are thousands - probably millions more that we haven't discovered yet. There are at least 2.5 million species of insects there. Imagine what would happen if they all lost their home? It couldn't happen, could it? Unfortunately, it's happening right now. Yet, the rainforest is big. But it's getting smaller. The problem is that people are cutting down the trees, mainly to make room for cows. These provide meat and make money for their owners. This process of cutting down trees is called ‘deforestation'.

The good news is that it is slowing down. In 2004, for example, more than 27,000 square kilometres were cut down. That's an area bigger than Wales. In 2006, because of all the campaigns to save rainforest, it dropped to just over 13,000 square kilometres. The bad news is that it's not enough. Scientists predict that by 2030, the rainforest will have become smaller by 40%. It's possible that by the end of the 21st century, the rainforest will have completely disappeared. With deforestation, thousands of the animals, birds, fish and plants that live in the Amazon rainforest lose their home, their natural habitat. Some of them move to other areas, but most of them die. Many species have already become extinct, and many more will if deforestation continues. That will change the balance of life in the rainforest and could cause enormous problems to the region's ecosystem.

There's another problem too. Trees and plants are a vital source of oxygen. If we cut them down, we lose that oxygen. But it's worse than just that. With deforestation, the trees and plants are burnt. This sends gases into the Earth's atmosphere, which stops some of the Earth's heat escaping. That then leads to the temperature here on the ground going up. This increase in the world's temperature is called 'global warming', and most scientists believe it's a very serious issue. If they stopped deforestation, it might help prevent global warming.

Question. What might help to restrain global warming?

A. increasing deforestation

B. stabilising deforestation

C. stop cutting down trees

D. clearing more trees for farming