About one million years ago,the Ice Age began.The Ice Age was a long period of time in which four great glaciers(冰川) pushed southward to cover almost all the upper half of North America,and then melted away.Each glacier was a thick sheet of ice and snow that spread out from a center near what is now Hudson Bay in Canada.The winters were long,and the cool summers were too short to melt much of the ice and snow.The ever?growing sheet built up to a thickness of two miles at its center.

As all glaciers do,these great glaciers slid(滑动). They pushed down giant trees in their paths and scraped(刮削)the earth bare(光秃秃)of soil.Many animals moved farther south to escape.Others stayed and were destroyed.

When winters of little snow came,the summer suns into the edges to the ice sheets.As the glaciers melted,rocks,soil and other things that had mixed with the ice and snow were left.New hills,lakes and rivers were formed.

The last of the great glaciers began its melting about 11 000 years ago.Itsmelting formed the Great Lakes.These lakes are today little changed from their early sizes the glaciers.This is the Mississippi Missouri Ohio system.These rivers were miles wide at first.Through the years they settle into their present channels.

The main idea of this passage is  ________ .

A.the Ice Age was a long period of time        

B.great glaciers covered North America many years ago        

C.changes in climate helped to melt the glaciers        

D.how glaciers changed North America       

2.The author states that all glaciers ________.

A.are two miles thick           B.form frozen lakes        

C.are a million years old      D.move and slide   

3.From the information in this passage we know that  ________.

A.glaciers are destructive        

B.all glaciers in the world move southward        

C.the Mississippi Missouri Ohio systems is larger than it was before the Ice Age        

D.the Great Lakes are now smaller than they were before the Ice Age

4.The Ice Age lasted almost ____.

A.1 000 years      B.100 years      C.1 000 000 years      D.11 000 years  

5.In the last sentence,the word “their” refers to  ________ .

A.lakes            B.rivers         C.glaciers             D.systems

Passage Fourteen(Antarctica and Environment)
Antarctica has actually become a kind of space station – a unique observation post for detecting important changes in the world’s environment. Remote from major sources of pollution and the complex geological and ecological systems that prevail elsewhere, Antarctica makes possible scientific measurements that are often sharper and easier to interpret than those made in other parts of the world.
Growing numbers of scientists therefore see Antarctica as a distant-early-warning sensor, where potentially dangerous global trends may be spotted before they show up to the north. One promising field of investigation is glaciology. Scholars from the United States, Switzerland, and France are pursuing seven separate but related projects that reflect their concern for the health of the West Antarctic Ice Sheet – a concern they believe the world at large should share.
The Transantarctic Mountain, some of them more than 14,000 feet high, divide the continent into two very different regions. The part of the continent to the “east” of the mountains is a high plateau covered by an ice sheet nearly two miles thick. “West” of the mountain, the half of the continent south of the Americas is also covered by an ice sheet, but there the ice rests on rock that is mostly well below sea level. If the West Antarctic Ice Sheet disappeared, the western part of the continent would be reduced to a sparse cluster of island.
While ice and snow are obviously central to many environmental experiments, others focus on the mysterious “dry valley” of Antarctica, valleys that contain little ice or snow even in the depths of winter. Slashed through the mountains of southern Victoria Land, these valleys once held enormous glaciers that descended 9,000 feet from the polar plateau to the Ross Sea. Now the glaciers are gone, perhaps a casualty of the global warming trend during the 10,000 years since the ice age. Even the snow that falls in the dry valleys is blasted out by vicious winds that roars down from the polar plateau to the sea. Left bare are spectacular gorges, rippled fields of sand dunes, clusters of boulders sculptured into fantastic shapes by 100-mile-an-hour winds, and an aura of extraterrestrial desolation.
Despite the unearthly aspect of the dry valleys, some scientists believe they may carry a message of hope of the verdant parts of the earth. Some scientists believe that in some cases the dry valleys may soak up pollutants faster than pollutants enter them.
1.What is the best title for this passage?
A.Antarctica and environmental Problems.
B.Antarctica: Earth’s Early-Warning station.
C.Antarctica: a Unique Observation Post.
D.Antarctica: a Mysterious Place.
2.What would the result be if the West Antarctic Ice Sheet disappeared?
A.The western part of the continent would be disappeared.
B.The western part of the continent would be reduced.
C.The western part of the continent would become scattered Islands.
D.The western part of the continent would be reduced to a cluster of Islands.
3.Why are the Dry Valleys left bare?
A.Vicious wind blasts the snow away.
B.It rarely snows.
C.Because of the global warming trend and fierce wind.
D.Sand dunes.
4.Which of the following is true?
A.The “Dry Valleys” have nothing left inside.
B.The “Dry Valleys” never held glaciers.
C.The “Dry Valleys” may carry a message of hope for the verdant.
D.The “Dry Valleys” are useless to scientists.

Culture helps human societies survive in changing natural environment．For example, the end of the last Ice Age, beginning about 15,000 years ago, brought a big challenge to which humans had to adapt．Before this time, large parts of the northern hemisphere were covered in great sheets of ice that contained much of the earth' s water．In North America, large animals that wandered the vast tundra （冰原） provided people with food and materials for clothing and simple shelters．When the earth became warm, large Ice Age animals disappeared, and many land areas were covered by rising sea levels from melting ice．But people survived, they developed new technologies and learned how to survive on new plant and animal species． Finally some people settled into permanent villages, durable houses and farms．

Cultural adaptation has made humans one of the most successful species on the planet． Through history, major developments in technology, medicine, and nutrition have allowed people to reproduce and survive in ever-increasing numbers．The global population has risen from 8 million during the Ice Age to about 6 billion today．

However, the successes of culture adaptation can also create problems in the long run．Over the last 200 years, people have begun to use large quantities of natural resources and energy and to produce a great amount of material and chemical wastes．The global population now consumes some important natural resources—such as petroleum, wood, and minerals—faster than nature can produce them．Many scientists believe that in the process of burning fuels and producing wastes, people may be changing the global climate in unpredictable and possibly harmful ways．Thus, the adaptive success of the present-day global culture of production and trade may be temporary．

1.What is the first paragraph mainly talking about?

2.To deal with the problems, human beings should ______according to the passage．

3.Which of the following is the problem caused by cultural adaptation according to the passage?

4.Which of the following can be the best tide of the passage?

On the first day of class, Mr Whiteson gave us a lecture about a creature(生物) called cattytiger, a kind of cat-like animal that completely disappeared during the Ice Age. He passed round a skull (头骨) as he talked, and we all felt interested and took notes while listening. Later, we had a test about that.

When he returned my paper, I was very, very surprised. There was a very large cross through each of my answers. And so it was with everyone else’s in our class. What had happened? Everyone was wondering and couldn’t wait to get the answer.

Very simple, Mr Whiteson explained. He had made up all that story about the cattytiger. There had never been such an animal. So why none of us noticed that and how could we expect good marks for the incorrect answers?

Needless to say, we got very angry. What kind of teacher was this?

We should have guessed it out, Mr Whiteson said. After all, at the very moment he was passing around the cattytiger skull (in fact, a cat’s), hadn’t he been telling us that it completely disappeared during the Ice Age? Clearly he was telling a lie. But we just kept busy making notes and none used his head. We should learn something from this. Teachers and textbooks are not always correct.

1. We failed in the test because we didn’t________.

A. take notes while listening

B. show interest in what Mr Whiteson said

C. listen to the teacher carefully

D. think carefully

2. We got angry because________.

A. Mr Whiteson didn’t tell us the truth about cattytiger

B. we failed in the test

C. we didn’t know why he played the joke on us

D. there was no cattytiger

3. Mr Whiteson gave us a special lesson________.

A. to show his special way of teaching

B. to play a joke on us

C. to help us learn our lessons better

D. so that we would no longer believe him

4. Mr Whiteson meant that________.

A. teachers couldn’t make any mistakes

B. textbooks might be wrong sometimes

C. we should speak up if we thought our teacher or the textbook was wrong

D. we shouldn’t believe our teachers because sometimes they might tell lies

On the first day of class, Mr Whiteson gave us a lecture about a creature(生物) called cattytiger, a kind of cat-like animal that completely disappeared during the Ice Age. He passed round a skull (头骨) as he talked, and we all felt interested and took notes while listening. Later, we had a test about that.
When he returned my paper, I was very, very surprised. There was a very large cross through each of my answers. And so it was with everyone else’s in our class. What had happened? Everyone was wondering and couldn’t wait to get the answer.
Very simple, Mr Whiteson explained. He had made up all that story about the cattytiger. There had never been such an animal. So why none of us noticed that and how could we expect good marks for the incorrect answers?
Needless to say, we got very angry. What kind of teacher was this?
We should have guessed it out, Mr Whiteson said. After all, at the very moment he was passing around the cattytiger skull (in fact, a cat’s), hadn’t he been telling us that it completely disappeared during the Ice Age? Clearly he was telling a lie. But we just kept busy making notes and none used his head. We should learn something from this. Teachers and textbooks are not always correct.
1. We failed in the test because we didn’t________.
A. take notes while listening
B. show interest in what Mr Whiteson said
C. listen to the teacher carefully
D. think carefully
2. We got angry because________.
A. Mr Whiteson didn’t tell us the truth about cattytiger
B. we failed in the test
C. we didn’t know why he played the joke on us
D. there was no cattytiger
3. Mr Whiteson gave us a special lesson________.
A. to show his special way of teaching
B. to play a joke on us
C. to help us learn our lessons better
D. so that we would no longer believe him
4. Mr Whiteson meant that________.
A. teachers couldn’t make any mistakes
B. textbooks might be wrong sometimes
C. we should speak up if we thought our teacher or the textbook was wrong
D. we shouldn’t believe our teachers because sometimes they might tell lies