16. We hope that as many people as-possible ____join us for the picnic tomorrow.
　　A. need B. must C. should D. can
17. There’s no light on----they be at home.
　　A. can’t B. mustn’t C. needn’t D. shouldn’t
18. -- May I smoke here ?
　　-- If you ____, choose a seat in the smoking section.
　　A. should B. could C. may D. must
19. ---How’s your tour around the North Lake? Is it beautiful?
　　---It ________ be, but it is now heavily polluted.
　　A. will B. would C. should D. must
20. –Tom, you didn’t come to the party last night?
　　–I ____, but I suddenly remembered I had homework to do.
　　A. had to B. didn’t C. was going to D. wouldn’t
21. --- She looks very happy. She ______ have passed the exam.
　　--- I guess so. It’s not difficult after all.
　　A. should B. could C. must D. might
22. My MP4 player isn’t in my bag. Where I have put it?
　　A.can B.must C.should D.would
23. —Where is my dictionary? I remember I put it here yesterday.
　　—You it in the wrong place.
　　A.must put B.should have put C.might put D.might have put
24. I told your friend how to get to the hotel, but perhaps I have driven her there.
　　A.could B.must C.might D.should
25. --- My cat’s really fat.
　　--- You ______ have given her so much food.
　　A. wouldn’t B. couldn’t C. shouldn’t D. mustn’t
26. In crowded places like airports and railway stations,you___ take care of your luggage.
　　A. can B. may C. must D. will
27. --What does the sign over there read?
　　-- “No person ________ smoke or carry a lighted cigarette，cigar or pipe in this area.”
　　A.will B.may C.shall D. must
28. The teacher __ have thought Johnson was worth it or she wouldn't have wasted time on him, I suppose.
　　A. should B. can C. would D. must
29. The biggest problem for most plants, which ________ just get up and run away when threatened, is that animals like to eat them.
　　A. shan’t B. can’t C. needn’t D. mustn’t
30. ---Turn off the TV, Jack. ____ your homework now?
　　---Mum, just ten more minutes, please.
　　A.Should you be doing B. Shouldn't you be doing
　　C. Couldn't you be doing D. Will you be doing