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问题 选择题

我国的“嫦娥”探月工程已正式启动．据科学家预测，月球的土壤中吸附着数百万吨的

3
2
He，全世界如果用“氦3”聚变发电，能用一万到五万年．在地球上，氦元素主要以
4
2
He的形式存在．下列说法正确的是（　　）

A．

4
2
He原子核内含有4个质子

B．

3
2
He与
4
2
He互为同位素

C．

3
2
He原子核内含有3个中子

D．

4
2He的最外层电子数为2，所以
4
2
He具有较强的金属性

答案

A、24He质子数为2，故A错误；

B、23He与24He质子数相同，质量数不同，为氦元素的不同原子，互为同位素，故B正确；

C、23He中子数为3-2=1，故C错误；

D、24He最外层电子数为2，但He只有1个电子层，为饱和稳定状态，He的性质稳定，几乎不表现金属性、非金属性，故D错误．

故选：B．

填空题

Part 4


Questions 26-45


·Read the following passage and choose the best word for each space.
·For questions 26-45, mark one letter A, B, C or D on the Answer Sheet.
During the past ten years (26) attention has been given to "telling it like it is". My impression is that this devotion to (27) one’s mind has more often led to hurt feelings and ruined relationships than (28) great joy.
I think we generally agree that never expressing real feelings and (29) all less-than-lovely thoughts about each other always leads to constructive communication. It’s a great (30) to allow ourselves to admit our human weaknesses and pursue more honest relationships with others. (31) we need to keep a balance between telling it all and telling nothing.
Recently I received a letter from a mother who had been (32) by her son to attend a weekend meeting with him. Under pressure from the group, her defenses cracked and she heard herself (33) her son for the first time that he (34) an accident—that she hadn’t been planning to have a child. He (35) told her that he couldn’t recall a single day in his childhood that he’d been happy. We cried and (36) ; I thought telling the truth had been good for us. But the trouble is, it wasn’t the whole truth. By the time Tommy was born I did want him, and at (37) he was happy. Ever since that day, we (38) . by some terrible feelings we exchanged. I must admit I’ve (39) the conclusion that some things are better left uncovered. Honesty is a fine policy, but we need a new sense of (40) . Disclosing is not a solution to every problem (41) even an end in itself. It’s useful under some circumstances and terribly hurtful under (42) . It’s a good idea, I think, to bite your (43) for ten or fifteen minutes before saying what’s (44) your mind. Try to decide whether it’s going to open up new and better ways of communication or (45) wounds that may never heal.

A．reluctance

B．release

C．relief

D．reflection
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单项选择题

在商品生产中，抽象劳动的特点不包括 ( )

A．反映了商品生产者之间的社会关系

B．体现着不同劳动的统一性

C．不同商品生产过程中的抽象劳动没有质的差别，只有景的不同

D．独立于具体劳动过程之外的劳动
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