766] The poor boy is in danger. We should do all we _____ help him out.

[译文] 那个可怜的孩子处于危险中。我们应该尽力帮助他。

　 A. can do 　 B. can to

　 C. can to do 　 D. can

[答案及简析] B。 这是一个常见结构，补充完整就是：We should do all we can do to help him out。

765] Nobody but you _____ able to sing that American song.

[译文] 除了你没有人能唱好这首美国歌曲。

　 A. are 　 B. were

　 C. is 　 D. can be

[答案及简析] C。 本句的主语是nobody，所以谓语动词用单数。

764] -----Have you _____ everything ready for the meeting? ----- Not yet, we need ______.

[译文] -- 你做好了一切会议的准备了吗？　--没有，还需要三把椅子。

　 A. got; another three chairs 　 B. got; more three chars

　 C. prepared; other three chairs 　 D. prepared; three another chairs

[答案及简析] A。 get sth. ready 做好了一切准备；another three chairs = three more chairs 。

763] It is he, not you, _____ right.

[译文] 是他对，而不是你对。

　 A. who are 　 B. who is

　 C. which is 　 D. that are

[答案及简析] B。 先行词是he，是单数而不是复数。

762] Those _____ know the answer put up your hands.

[译文] 那些知道答案的请把手举起来。

　 A. who 　 B. which

　 C. that 　 D. whom

[答案及简析] A。 先行词为those时，关系代词用who。

761] It’s only ten minutes ______ the meeting but he’s still not here yet.

[译文] 直到开会前十分钟，他都还没有到。

　 A. for 　 B. at

　 C. by 　 D. till

[答案及简析] D。 for后接一段时间；at表示具体时间；by 表示到…为止或在…之前；till表示直到…，时态用一般时态。

760] By the time he was twelve he ______ a chemistry lab of his own.

[译文] 到他12岁的时候，他就建起了他自己的实验室。

　 A. built 　 B. has built

　 C. had built 　 D. was building

[答案及简析] C。 有by the time 引导的短语或从句，主句应该是完成时态，至于是什么完成时态，就看by短语或从句中的时态了。

759] David jumped _____ to get the first ______ the beginning of the sports.

[译文] 在运动会的开头，David就跳得很高得到了第一名。

　 A. enough high; in 　 B. enough highly; in

　 C. high enough; at 　 D. highly enough; at

[答案及简析] C。 enough 是副词，那么当它修饰其它词类时，应该放在被修饰词的后面；在什么的开头，介词用at。

758] Who is the singer ______ you like best?

[译文] 你最喜欢的歌手是谁？

　 A. that 　 B. who

　 C. whom 　 D. which

[答案及简析] A。 以who, which 引导的句子，定语从句只能用that。

757] Whose turn ___ the cleaning?

[译文] 该谁做清洁了？

　 A. is it doing 　 B. is it to do

　 C. is doing 　 D. is to do

[答案及简析] B。 句型it is one’s turn to do sth.的特殊疑问句形式。