40. He doesn't know ____ to stay or not.

　　　 A. whether　　　　 B. if　　　　 C. either　　　　 D. if he will

39. There isn't any difference between the two. I really don't know ____ .

　　　 A. where to choose　　　　　　 B. which to choose

　　　 C. to choose what　　　　　　　 D. to choose which

16. The purpose of new technologies is to make life easier, _________ it

　　　 more difficult.

　　　 A. not make　　　　　 B. not to make

　　　 C. not making　　　　 D. do not make

不定式：

　　 to加动原不定式，非谓不做谓语用，功能如同名形副，疑问副代可连用，宾补有to分两种，前面加not是否定

疑问代词：what / who / which + to do

疑问副词：whether / when / where / how + to do

疑问代词：what / who / which + to do(及物)(疑问代词做不定式的宾语)

　　 I don't know who to invite.

疑问副词：whether / when / where / how + to do

　　 I don't know how to invite her.

　　 what和which的区别：

　　　 　不知道具体什么东西时用what

　　　　 前面有个范围可供选择用which，无范围用what

11. Strangely enough, a pair of new trousers ______ among the rubbish.

　　　 A. were found　　　　 B. was found

　　　 C. has found　　　　　 D. have found

12. Few pleasures can equal ___________ of a cool drink on a hot day.

　　　 A. some　　　　　　　　　 B. any

　　　 C. that　　　　　　　　　　 D. those

7. ____________ him and then try to copy what he does.

　　 A. Mind　　　　　　　　 B. Glance at

　　 C. Stare at　 　　　　　　D. Watch

6. _________ you've got a chance, you might as well make full use of it.

　　 A. Now that　　　　　　　　　 B. After

　　 C. Although　　　　　　　　　 D. As soon as

now that　 既然

4. -Are the new rules working?

　　 -Yes. ____________ books are stolen.

　　 A. Few　　　　 B. More　　　　 C. Some　　　　 D. None

3. Paper money was in ________ use in China when Marco Polo visited

　　 the country in _______ thirteenth century.

　　 A. the; 不填　　　　　　　 B. the; the

　　 C. 不填; the　　　　　　　 D. 不填; 不填

19. John may phone tonight. I don't want to go out ______ he phones.

　　　 A. as long as　　　　 B. in order that　　　　 C. in case　　　　 D. so that