54.He _________ his bike so he has to walk there.

　A. lostB. has lostC. had lostD. loses

　答案：B　(选择A的同学注意句子并没出现两个时间点，因此要注意时态的前后一致.)

53..– How many books _____ they ________?

　-- Five. But they haven’t finished reading even one.

　A. did…borrowB. had…borrowedC. will…borrowD. do…borrow

　答案：A　(选择B的同学要注意，这里只是问过去发生的一件事，并不是过去时间之前发生的.)

52..The train _________ for twenty minutes.

　A. leftB. has leftC. is leavingD. has been away

　答案：D　(选择B的同学要注意，当用完成时表示持续动作时，要选择可持续动词，不要用瞬间动词.)

51.The pen _________ him ten yuan.

　A. paidB. costC. tookD. spent

　答案：B　(选择C的同学要注意took通常用在时间上；选择A和D的同学要注意，这里的主语是物品，因此不能用paid 和spent)

50..He will call me as soon as he _________ the city.

　A. reachesB. reachedC. will reachD. is reaching

　答案：A　(选择B的同学要注意主将从先)

49..If you have lost a library book, you have to _________ it.

　A. find outB. look afterC. pay forD. take care

　答案：C　(选择A的同学要注意语境)

48.– I called you last night but no one answered the phone.

　-- I ________ dinner with my friends in the restaurant.

　A. haveB. hadC. was havingD. have had

　答案：C　(选择B和D的同学要注意分析语境.这里指我当时正在和朋友在饭馆吃饭.)

47..If anyone wants to say something in class, you ________ put up your hands first.

　A. mustB. mayC. shouldD. can

　答案: A ( 选其他三个选项的同学要注意语境，anyone暗示出语气。表明是一个规定，而不是建议。)

46.It is in the library, you _______ talk loudly.

　A. may notB. can’tC. needn’tD. mustn’t

　答案: D ( 选择B的同学要注意中文的干扰.can’t表示不能够。)

45..Though it’s cloudy now, it _________ get sunny later.

　A. can B. mayC. mustD. need

　答案: B ( 选C的同学要注意语境, 这里强调过些时候也许会晴天, 表示推测性.)