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1. It's said that the long bridge        in two months.

in detail  there is no truth to  there is no comparison  in the absence of  it is necessary that

1. I think I have made myself clear.         between the two things.

2.        any of these statements,and they haven't been mentioned by the company.

3. Tom has told me what happened       .

4.        you should make your choice very carefully.

5. The suspect was set free        firm evidence.

  Most musicians agree that the best violins were made in Cremona,Italy, about 200 years ago. They even sound better than violins made today. Violin makers and scientists try to make instruments like the old Italian violins. But they aren't the same. Why are these old Italian violins so special? Many people think they have an answer.

  Some people think it is the age of the violins. But there is a problem here. Not all old violins sound wonderful. Only those from Cremona are special. So age cannot be the answer.

  Other people think the secret to those violins is the wood. The wood of the violin is very important. It must be from certain kinds of trees. It must not be too young or too old. Perhaps the violin makers of Cremona knew some?thing special about wood for violins.

  But the kind of wood may not be so important. It may be more important to cut the wood in a special way. Wood for a violin must be cut very carefully. It has to be the right size and shape. The smallest difference will change the sound of the violin.   Musicians sometimes think that this is the secret of the Italians.

  Size and shape may not be the answer either. Scientists make new violins that are exactly the same size and shape. But the new violins still do not sound as good as the old one. Some scientists think the secret may be the varnish (清漆) ，which covers the wood of the violin and makes it look shiny. It also helps the sound of the instrument. Since no one knows what the Italian violin makers used in their varnish,no one can make the same varnish today.

There maynever be other violins like the violins of Cremona. And there are not many of the old violins left. So these old violins are becoming more and more precious.

5. What would be the best title for the passage?

   A. The secrets of Cremona violins

   B. The history of Italian violins

   C. Special musical instruments

   D. How to make the best violins

6. Other people think the Italian violin makers         .

   A. were lucky

   B. did not know much about the violins

   C. used many kinds of wood

   D. knew something special

7. What is still unclear about Cremona violins according to the writer?

   A. The shape. B. The size.

   C. The wood. D. The varnish.

8. What can we learn from this passage?

   A. Modern things are always better than ancient ones.

   B. Ancient things are always better than modern ones.

   C. Once a cultural relic is lost,it can never be recovered.

   D. Varnish for violins will become more and more precious.

  A Antarctica has actually become a kind of space station―a unique observa?tion post for detecting important changes in the world's environment. Remote from major sources of pollution and the complex geological and ecological sys?tems that prevail elsewhere,Antarctica makes possible scientific measure?ments 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 theUnited States,Switzerland,andFranceare 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 Mountains,some of them more than 14,000 feet high,divide the continent into two very different regions. The part of the con?tinent 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 theAmericasis 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 disap peared,the western part of the continent would be reduced to a sparse (稀疏的) group of island.

  While ice and snow are obviously central to many environmental experi?ments,others focus on the mysterious dry valleys of Antarctica,valleys that contain little ice or snow even in the depths of winter. Slashed (揮砍) 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 blown out by vicious winds that roar down from the polar plateau to the sea. Left bare are spectacular gorges,rippled (起伏的) fields of sand dunes,groups of boulders (卵石) sculptured into fantastic shapes by 100-mile-an-hour winds.

  Despite the unearthly aspect of the dry valleys,some scientists believe they may carry a message of hope of the green parts of the earth. Some scien?tists 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 earlywarning 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 sparse group of island

3. Why are the "dry valleys" left bare?

   A. Because vicious wind blasts the snow away.

   B. Because it rarely snows.

   C. Because of the global warming trend and fierce wind.

   D. Because of the 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 green.

   D. The dry valleys are useless to scientists.

as well as  be always  in case of  in particular  keep one's balance

1. Tom        his brother is a doctor.

2. Stricter safety measures will be taken at the airport        new terrorist attacks.

3. I was moved by the whole performance and the dance by the disabled girl      

4. He        forgetting where he leaves his things.

5. The teacher said that it was important to        when I made a sequence of dance movements.

5. She        (walk) along the street when she heard her name called.

4. The family        (watch) TV now.

3. The first man        (set) foot on the moon was Armstrong.

2. This kind of cloth        (sell) well.

1. A treaty        (sign) by the two countries about the border last year.