31. -I’m sure Andrew will win the first prize in the final.

　-I think so. He ________ for it for months.

A. is preparing　 B. was preparing　 C. has been preparing　 D. had been preparing

30. The teacher stressed again that the students should not ________ any important details while retelling the story.

A. figure out　　 　　 　　B. let out　　 　　　　C. leave out 　 　　　　D. pick out

29. -The guard keeps 　　　　　watch at the gate.

　-So he does. Only those 　　　　　knows well could be let in.

A. close; who　 　　　　　　 B. tight; whom　 　　　　　 C. tight; that　 　　　　　　 D. close; he

28. He _______ have escaped, but he chose to stay and fight.

　 A. must　　 　　　　　　 B. could　 　　　 　　　　C. will　　 　　　　 　　　 D. need

27. _______, according to the instructions, the medicine, I think, will work on your headache before long.

　 A. Take　　　　　　　 B. Being taking　　　 C. Taken　　　　　 　　 D. Taking

26. Only after spending several nights working on the math problem 　　　　　to wonder whether the problem was wrongly set.

A. had he begun　　 　　　 B. he began　 　　　　　　 C. did he begin　 　　　　 D. began he

25. I can’t persuade him out of playing computer games. He is 　　　　　to them.

A. reminded　 　　　　　　　　 B. accustomed　　 　　　　 C. addicted　 　　　　　　　 D. stuck

24. ______ by a greater demand of vegetables, farmers have built more green houses.

A. Driven　　　　　　 B. Being driven　　　 　 C. To drive　　 　 D. Having driven

23. It is reported that the floods have left about _________ people homeless.

A. two thousand　　　　 B. two-thousands　　 C. two thousands　 　　　 D. two thousands of

22. When you get the paper back, pay special attention to what ________.

A. have marked　　 　　　 　　B. have been marked　 C. had marked　　 　　　 D. had been marked