21. Generally, the thicker a mammal’s (哺乳動(dòng)物) skin is, the less hair ______.

　　A. that has it B. that it has C. has it D. it has

　　22. My father ______ an invitation to a dinner party, but he _______ it.

　　A. accepted…received B. received…accepted

　　C. accepted…didn’t receive D. received…didn’t accept

　　23. _______ their homework, the children went for a walk.

　　A. When they were doing B. After they have done

　　C. Having done D. They had done

　　24. My parents never let me _______ alone.

　　A. to travel B. to travelling C. travelling D. travel

　　25. Hardly _______ the classroom when the class began.

　　A. had he entered B. he had entered C. he entered D. he was entered

　　26. We all enjoy working _______ him because he is a kind leader.

　　A. along B. in C. under D. on

　　27. She is _______to refuse, so I have to give in.

　　A. a too kind girl B. too a kind girl

　　C. too kind a girl D. a gird kind too

　　28. He couldn’t use his own car because it ________ then.

　　A. was being repaired B. was repairing

　　C. is repairing D. has been repaired

　　29. _______ go to the Great Wall for a visit?

　　A. Why don’t B. How about C. Will we D. Why not

　　30. With the guide ______ the way, we set out on foot into the night dark.

　　A. lead B. leading C. led D. to lead

　　31. He seems _______ from this university.

　　A. graduating B. being graduated C. to graduate D. to have graduated

　　32. The refugees need many things, but _______, they need food and medicine.

　　A. at most B. above all C. after all D. at the first

　　33. ______ France Viuard an excellent political speaker but she was also among the first members of the populist party.

　　A. Not only B. If only C. Only D. Not only was

　　34. He failed in the examination three times but _______ he passed.

　　A. at end B. at finish C. at last D. at least

　　35. On his return from his college, he found the house ________.

　　A. deserting B. deserted C. desert D. to be deserted

　　36. When Jane fell off the bike, the other children ________.

　　A. were not able to help laughter B. could not help but laughing

　　C. could not help laughing D. could not help to laugh

　　37. English is _______ interesting to us.

　　A. much B. very C. very much D. more

　　38. Grammar books here _______ well.

　　A. are sold B. sell C. sells D. have been sold

　　39. If everybody is _______, let’s begin our class.

　　A. sat B. seated C. seat D. sitted

　　40. He must have been there before, ________?

　　A. hasn’t he B. haven’t he C. doesn’t he D. isn’t he