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• 1The following examples except _______________ reflect man altering the balance of nature．

  A.man is covering huge areas with new kinds of plants

  B.man is facilitating the spread of animals into new regions．

  C.man is killing some species on a large scale

  D.man is getting to know the importance of keeping the balance of nature．

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• 2Which of the following statements about microwave heaters would Buffler most probably agree with、

  A.Microwave heaters will soon be widely used by homeowners.

  B.Microwave heaters sometimes make people feel uncomfortable.

  C.Perhaps microwave heaters will be first used by livestock farmers, who wish to protect their lambs in winter.

  D.Microwave heaters cannot be accepted by the public because they are somewhat unsaf

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• 3According to Paragraph 4, which of the following fills the room with low-power microwaves、

  A.The magnetron.

  B.The motion detector.

  C.The microwave oven.

  D.The radiation-absorbing chemical.

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• 4The test conducted by Buffler shows that when a person feels comfortable warmth, he receives about ________________.

  A.20 mw. / sq. cm.

  B.40 mw. / sq. cm.

  C.60 mw. / sq. cm.

  D.85 mw. / sq. cm.

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• 5According to Paragraph 2, which of the following does not describe the characteristics of a microwave heater、

  A.It directly heats people in a room.

  B.It heats walls and furniture in a room.

  C.It is safe.

  D.It saves energy．

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• 6What have spread diseases、

  A.Disease-sleeping sickness．

  B.Measles．

  C.Improved communications．

  D.Malaria．

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• 7We make a nature sanctuary for rare birds but _______________.

  A.some common and hardy kind of bird multiplies

  B.rare kinds multiply

  C.all bird multiply

  D.no bird multiply

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• 8The main idea of the passage is ______________．

  A.that man is deliberately destroying the balance of nature

  B.that man has foreseen the consequences of altering the balance old nature

  C.that improved communications have changed history

  D.that man is altering the balance of nature

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• 9According to the author, a bachelor resists marriage chiefly because ____________ .

  A.he is reluctant to take on family responsibilities

  B.he believes that life will be more cheerful if he remains single

  C.he finds more fun in dating than in marriage

  D.he fears it will put an end to all his fun adventure and excitement

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• 10Raising children, in the author’s opinion is ____________ .

  A.a moral duty

  B.a thankless job

  C.a rewarding task

  D.a source of inevitable pain

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