31. I haven’t seen Molly this week. I think she _____ her parents but I’m not sure.

　 A. might be visiting　　　　　　　 B. ought to visit　

C. could have visited　　　　　　 D. had better visit

30.____ all her shopping, Lucy decided to go for a cup of coffee and have a rest.

　 A. Doing　 B. Being done　 C. Having done　 D. Having been done

29. It was a workday morning, and ____ must have been kids in school then.

　 A. there　　 B. it　 C. that　 D. which

28. It was the training ____ he had as a young man ____ made him such a good engineer.

　 A. what; that　　 B. that ; what　　 C. that; which 　　D. which; that

27. With more and more forests being destroyed, huge quantities of good soil in our country ______.

　 A. had been washed away　　 B. has been washed away　

　 C. were washed away　　　 D. are being washed away

26. There is a new problem involved in the popularity of private cars _____ road conditions need _____.

　 A. that; to be improved　 B. which; to be improved　

C. where; improving　　 D. when; improving

25. She didn’t come to the party last Sunday. ________, she could have made the party more exciting.

　 A. If she came　 B. Would she come　 C. Had she come　 D. Did she come

24. She learnt both business and history, but she knows _____ of them well, though she can speak on _____ subjects in general.

　 A. none; any　 B. nothing; anything　 C. neither; both　 D. either; neither

23. I wonder if Europeans make ____ a rule to send cards to their friends before Christmas.

　 A. themselves　　 B. it　 C. that　 D. this

22. ______ has just been explained is the key to the successful completion of the task.　 A. That　　 B. Which　　 C. What　　 D. This