53. He paid for a seat, when he ______ have entered free.　　　　 　(Shangdong 2005)

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

52. -Catherine, I have cleaned the room for you.　　　　　　　　 　(Fujian 2005)

　 -Thanks. You 　　　　　it. I could manage it myself.

　 A．needn’t do　 B．needn’t have done C．mustn’t do　 D．shouldn’t have done

51. This cake is very sweet. You __________ a lot of sugar in it. (Liaoning 2005)

　 A．should put　 B．could have put　 C．might put　 D．must have put

50. ---- Don't you think it necessary that he ____ to Miami but to New York?

---- I agree, but the problem is ________ he has refused to. (Jiangshu 2005)

A. will not be sent; that　　　　　 B. not be sent; that

C. should not be sent; what　　　　 D. should not send; what

49. ---- The woman biologist stayed in Africa studying wild animals for 13 years before she returned.　

----Oh, dear! She _______ a lot of difficulties!　　　　　　　　 (Jiangshu 2005)

A. may go through　　　　　　　　　 B. might go through

C. ought to have gone through　　　 D. must have gone through

48. If I　 　　　plan to do anything I wanted to, I’d like to go to Tibet and travel through as much of it as possible.　

A．would　 　　　　　B．could　 　　　C．had to　 D．ought to (Hubei 2005)

47. -Do you know where David is? I couldn’t find him anywhere.　　 　　(Hubei 2005)

　　 -Well . He 　　　have gone far-his coat’s still here.

　　 A．shouldn’t　 B．mustn’t　 C．can’t　　　　 D．wouldn’t　

46. I have lost one of my gloves. I 　　　　it somewhere.　　　　　　 (Beijing 2005 spring)

A. must drop　　 B. must have dropped C. must be dropping D. must have been dropped

45. He _____ have completed his work; otherwise, he wouldn’t be enjoying himself by the seaside.

A. should　　　　　 B. must　　　 　　 　C. wouldn’t　　 　　D. can’t (Beijing 2005)

44. Helen 　　　　go on the trip with us, but she isn’t quite sure yet.(Anhui 2005)

A. shall　　　　　 B. must　　　　 　C. may　　　　　　 　D. can