1. 解析：选D。would have done表示对过去已发生的事情的推测，表示“可能……”，故最佳答案是D项。

10. The students who do best in the examination are not always 　　　with the best brains.

A. the ones　 B. these　 C. them　 D. that

9. -Why did you stop writing?

-My ink has　　　 .

A. used up　　　 B. run out of

C. given away　 D. given out

8. I 　　　all my homework by the time you 　　　back.

A. will have finished; come

B. will finish; come　

C. will have finished; came

D. have finished; will come　

7. -How could I thank you enough?

-Don’t mention it. Any other man 　　　that.

A. must do　　　　　　 B. could do

C. would have done　　 D. should have done

6. When he was still a child,he　　 in the river, but now he no longer swims in it.

A. was used to swimming　　 B. used to swim

C. was used to swim　　　　 D. used to swimming

5. -I drove to Zhuhai for the air show last week.

-Is that the reason 　　　you had a few days off?

A. why　　 B. When　　 C. what　 D. where

4. It is certain that he will　　　 　his business to his son when he gets old.

A. take over　 B. think over

C. hand over　 D. go over