Although the causes of cancer ______, we do not yet have any practical way to prevent it.

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• 1The scholar ______ to work the other day, so he stayed in bed until 10 o’clock.

  A.didn’t need to go

  B.needn’t have gone

  C.mustn’t go

  D.shouldn’t have gone

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• 2There are so many models ______, but I’m at a loss which to buy.

  A.to be chosen

  B.to choose from

  C.to choose

  D.for choosing

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• 3What can we learn from the speech、

  A.Ground travel can offer as many services as air travel.

  B.Air travel offers more and better services than ground travel.

  C.Ground travel can sometimes offer more services than air travel.

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• 4What was the speaker once doing、

  A.She was working on a bus.

  B.She was working on a plane.

  C.She was working as a cook.

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• 5Why is the speaker surprised at the services、

  A.The services include some sandwiches.

  B.The services include rest rooms as well as food.

  C.The services include some good music.

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• 6A great number of people like ______ programme “Discovery”, ______ programme which can help them learn much about the world.

  A.a, the

  B.a, a

  C.the, a

  D.the, the

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• 7They lit a fire to ______ wild animals.

  A.keep away

  B.keep off

  C.keep up

  D.keep back

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• 8If it had been fine yesterday, we could have watched that air show. But it ______ all day.

  A.has rained

  B.rains

  C.rained

  D.had rained

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• 9The big fire in Shanghai, which was believed to _____ due to the burning of construction materials, caused 58 deaths and destroyed all the belongings of the people there．

  A.have occurred

  B.occur

  C.have been occurring

  D.be occurring

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• 10The young man suggested the problem worth paying attention _____ at the meeting.

  A.to be discussed

  B.to been discussed

  C.being discussed

  D.be discussed

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