12. You have to get there before eight o’clock. You __________ now.
A. need go B. need to go
C. need have gone D. need to have gone
答：B。need做情态动词用时，仅用于疑问或否定句中。
13. A computer__________ think for itself~ it must be told what to do.
A. can’t B. couldn’t
C. may not D. might not
答：A。can表示“能力”。
14. —Shall we go skating or stay at home?
—Which _______do yourself?
A. do you rather B. would you rather
C. will you rather D. should you rather
答：B。 would rather (not) do 宁愿(不)做
15. Tom ought not to _______ me your secret, but he meant no harm.
A. have told B. tell
C. be telling D. having told
答：A。ought not to have done 本不应该做但实际上做了的事
16. The new airport___________ if they had not stopped working on it.
A. would complete
B. had been completed
C. had completed
D. would have been completed
答：D。从句为过去完成时，主句应用“would(should，mlgh，could)+现在完成式”，表示与过去事实相反的虚拟语气。
17. I didn’t see her in the meeting room this morning. She___________ at the meeting.
A. mustn’t have spoken
B, shouldn’t have spoken
C. needn’t have spoken
D. couldn’t have spoken
答：D。表示“一定不”，应用couldn’t。must仅用于肯定句中表示推测，故排除A项。
18. Peter _____ come with us tonight, but he isn’t very sure yet.
A. must B. may C. can D. will
答：B。从后一句 he isn’t very sure yet 可判断B项，may可能。
19. —Shall I tell John about it?
—No, you ________. I’ve told him already.
A. needn’t B. wouldn’t
C. mustn’t D. shouldn’t
答：A。从后一句“我已经告诉他了”可判断“不必”。
20. —Don’t forget to come to my birthday party tomorrow.
—_________.
A. I don’t B. I won’t
C. I can’t D. I haven’t
答：B。I won’t. 我不会忘。
21. —There were already five people in the car but they managed to take me as well.
—It ________ a comfortable journey.
A. can’t be B. shouldn’t be
C. mustn’t have been D. couldn’t have been
答：D。从题干中的时态可判断出是对过去情况的推测。
22. One ought ______ for what one hasn’t done.
A. not to be punished B. to not be punished
C. to not punished D. not be punished
答：A。ought to的否定式为 ought not too
23. That young man has made so much noise that he _________ not have been allowed to
attend the concert.
A. could B. must
C. would D. should
答：D。should not have done 本不该做但实际上做了的事
14. It’s nearly seven o’clock. Jack ________ be here at any moment.
A. must B. need C. should D. can
答：C。只要抓住nearly这个信息词和后面at any moment 这个信息词语就可以选出C项。 at any moment 相当于 very soon now。