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问题 选择题

钛合金是21世纪重要的金属材料，具有优良的性能．，如熔点高、密度小、可塑性好、机械性能好、抗腐蚀能力强，且钛合金与人体有很好的“相容性”．根据钛合金的主要性能，下列不符合实际的用途是（　　）

A．用于核潜艇设备的制造

B．用于做保俭丝

C．用于制造航天设备

D．用于制造人造骨

答案

A、用于潜艇设备的制造是因为它的密度小、可塑性好、机械性能好、抗腐蚀性强，故A符合实际的用途．

B、不能做保险丝，因为它的熔点高，故B不符合实际的用途．

C、用于制造航天设备是因为它的熔点高、密度小、可塑性好、机械性能好、抗腐蚀性强，故C符合实际的用途．

D、用于制造人骨替代品是因为它的合金与人体有良好的“相容性”，故D符合实际的用途．

故选B．

选择题

填入下文横线处正确的一项是（）

　　认真阅读的结果，不但随时会发现晶莹的宝石，____。于是收取那些值得取的，排除那些无足取的，自己才会渐渐地成长起来。

A．还会发现价值连城的钻石

B．也随时会发现粗劣的瓦砾

C．还常常会发现粗糙的砂砾

D．也不免会发现令人遗憾的败笔
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单项选择题

The "standard of living" of any country means the average person’s share of the goods and services which the country produces. A country’s standard of living, (1) , depends first and (2) on its capacity to produce wealth." Wealth" in this sense is not money, for we do not live on money (3) on things that money can buy. "Goods" such as food and clothing, and "services" such as transport and " (4) ". A country’s capacity to produce wealth depends upon many factors, most of (5) have an effect on one another. Wealth depends (6) a great extent upon a country’s natural resources. Some regions of the world are well supplied with coal and minerals, and have a fertile soil and a (7) climate; other regions possess none of them.

Next to natural resources (8) the ability to turn them to use. China is perhaps as well (9) as the USA in natural resources, but suffered for many years from civil and (10) wars, and (11) this and other reasons was (12) to develop her resources. (13) and stable political conditions, and (14) from foreign invasion, enable a country to develop its natural resources peacefully and steadily, and to produce more wealth than another country equally well (15) by nature but less well ordered.

A country’s standard of living does not only depend upon the wealth that is produced and consumed (16) its own borders, but also upon what is indirectly produced through international trade. (17) , Britain’s wealth in foodstuffs and other agricultural products would be much less if she had to depend only on (18) grown at home. Trade makes it possible for her surplus manufactured goods to be traded abroad for the agricultural products that would (19) be lacking. A country’s wealth is, therefore, much influenced by its manufacturing capacity, (20) that other countries can be found ready to accept its manufactures.

1（）

A.however

B.therefore

C.nevertheless

D.furthermore
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