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问题 填空题

下列事实分别说明空气中含有哪些成分？

（1）蜡烛能在空气中燃烧______；

（2）豆科植物可以利用空气合成氮肥______；

（3）酥脆的饼干在空气中放置一段时间会变软______．

答案

（1）常见的燃烧需要有氧气参与完成，所以该现象真名空气中含有氧气．

故答案为：氧气．

（2）豆科植物具有固氮功能，可用氮气合成氮肥，故此现象说明空气中含有氮气．

故答案为：氮气．

（3）酥脆的饼干在空气中放置一段时间会变软，是因为在空气中吸收了水蒸气导致的，所以证明了空气中含有水蒸气．

故答案为：水蒸气．

单项选择题

Modern liberal opinion is sensitive to problems of restriction of freedom and abuse of power. (1) , many hold that a man can be injured only by violating his will, but this view is much too (2) . It fails to (3) the great dangers we shall face in the (4) of biomedical technology that stems from an excess of freedom, from the unrestrained (5) of will. In my view, our greatest problems will be voluntary self-degradation, or willing dehumanization, as is the unintended yet often inescapable consequence of sternly and successfully pursuing our humanization (6) .

Certain (7) and perfected medical technologies have already had some dehumanizing consequences. Improved methods of resuscitation have made (8) heroic effort to "save" the severely ill and injured. Yet these efforts are sometimes only partly successful: They may succeed in (9) individuals, but these individuals may have sever brain damage and be capable of only a less-than-human, vegetating (10) . Such patients have been (11) a death with dignity. Families are forced to bear the burden of a (12) "death watch".

(13) the ordinary methods of treating disease and prolonging life have changed the (14) in which men die. Fewer and fewer people die in the familiar surroundings of home or in the (15) of family and friends. This loneliness, (16) , is not confined to the dying patient in the hospital bed. As a group, the elderly are the most alienated members of our society: Not yet (17) the world of the dead, not deemed fit for the world of the living, they are shunted (18) . We have learned how to increase their years, (19) we have not learned how to help them enjoy their days. Yet we continue to bravely and feverishly push back the frontiers (20) death.

6（）

A.functions

B.goals

C.purposes

D.origins
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单项选择题

美国财政部和商务部1月26日宣布，美国进一步放松对（）出口和旅行的相关限制，涉及民航、电信、防灾减灾、农业生产、公共交通和基础设施建设等多个领域。新规定将于27日开始生效。

A.古巴

B.俄罗斯

C.瑞士

D.法国
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