21. Sally looks very happy. She ________ have got the first place in the 200­metre race.

　　A. should B. could

　　C. must D. might

　　[解析]本题考查“情态动词+have done”。句意：Sally 看上去很高兴。她200米赛跑肯定得第一名了。should have done，“本应该干而事实上没干”;could have done 有两层含义：一表示过去可能干过;二表示过去本能够干某事(而事实上没干);must have done“过去肯定干过”;might have done 亦有两层含义：一表示过去或许干过;二表示过去本可以干某事(而事实上没干);由语境可知C项正确。

　　[答案]C

　　22.—Show me your permit, please.

　　—Oh, it's not in my pocket. It ________.

　　A. might fall out B. could fall out

　　C. should have fallen out D. must have fallen out

　　[解析]句意：—请出示许可证。—噢，不在我口袋里。肯定是掉出来了。由语境可知，fall out 动作应发生在过去，因为现在许可证不在口袋里，故应用“情态动词+have done”，排除A、B两项;should have done“本应该干某事(而事实上没干)”，不符合句意;故正确答案为D项，指“过去肯定干过”。

　　[答案]D

　　23.—Tom hasn't turned up yet. He might have got lost.

　　—No, he ________. His car has got a GPS.

　　A. must not have got lost B. wouldn't have got lost

　　C. can't have got lost D. shouldn't have got lost

　　[解析]本题考查 “情态动词+have done”。句意：—汤姆还没到这。他可能迷路了。—不，他不可能迷路。因为他的车上装有GPS定位系统。must 表推测时只用于肯定的陈述句，故A项予以排除;wouldn't have done“不会……”，只用于虚拟语气;can't have done“过去不可能干过”;shouldn't have done“本不应该干某事而事实上已经干了”;由句意可知C项正确。

　　[答案]C

　　24.—Where is Bob? I cannot find him anywhere.

　　—He ________ have been off long. I heard him make a call just now.

　　A. shouldn't B. can't

　　C. mustn't D. needn't

　　[解析]本题考查“情态动词+have done”。句意：—鲍勃哪里去了?我到处找不到他。—他不可能离开久了。我刚才还听见他打电话了。shouldn't have done“本不应该干某事(而事实上已干了)”;can't have done“不可能干过”;must 表推测不能用于否定句，故C项错误;needn't have done“本没有必要干某事(而事实上已干了)”;由语境可知B项正确。

　　[答案]B

　　25.He ________ a big fortune, but he was too lazy to seize the opportunity.

　　A. can have made B. could have made

　　C. must have made D. ought have made

　　[解析]本题考查“情态动词+have done”。can have done“过去可能干过”，一般不用于肯定的陈述句。could have done 意义有二：一表示“过去可能干过”;二表示“过去本能够干某事而事实上没干”;must have done“过去肯定干过”;D项表述错误，应为 ought to have done表示“本应该干某事而事实上没干”;由句意“他本来能够挣大钱，但他太懒没抓住机会”可知B项正确。

　　[答案]B

　　26.—Do you still remember the day when we went to the Great Wall?

　　—I can't remember it well, but ________ it have been sometime last year?

　　A. would B. must

　　C. could D. should

　　[解析]本题考查“情态动词+have done”。句意：—你还记得我们去长城的那一天吗?—我记不太清了，是不是去年的某个时候?由语境可知，这是对过去某个时间的推测，并且用于疑问句，故只能选 could。

　　[答案]C

　　27.What a pity! Considering his intelligence and diligence, he ________ a higher grade.

　　A. can have achieved B. must have achieved

　　C. need have achieved D. might have achieved

　　[解析]本题考查“情态动词+have done”。can have done“过去可能干过”，一般不用于肯定的陈述句;must have done，“过去肯定干过”;might have done 意义有两层：一表示“过去可能干过某事”;二表示“过去本可能干某事而事实上没干”;由句意“真遗憾!鉴于他的智力和努力，他本来能够获得一个更高一点的分数”可知D项正确。

　　[答案]D

　　28.—Where is my dictionary? I remember I put it here yesterday.

　　—Perhaps, you ________ it in the wrong place.

　　A. must have put B. should have put

　　C. can have put D. might have put

　　[解析]本题考查情态动词。must have done 表示对过去行为的推测，具有较大的可能性，意为“一定……;想必……”;should have done 表示应该做的事情没有做;can have done 表示过去可能做过。might have done 常用于推测过去的行为，表示“可能已经”;还可以表示过去应该做而没有做的事。由句意：“—我的词典呢?我记得我昨天放这儿了。—或许你放错了地方”可知D项正确。

　　[答案]D

　　29.—Sorry, the tickets have already been sold out.

　　—Really? Maybe I ________ a little earlier.

　　A. should come B. should have come

　　C. could have come D. must have come

　　[解析]本题考查“情态动词+have done”。句意：—抱歉，票早已卖完。—真的吗?或许我该早一点来。由语境可知，come 动作发生在过去，应用“情态动词+have done”，排除A项;should have done“本应该干某事而事实上没干”，符合语境;could have done“本能够干而实际上没干”;must have done“过去肯定干过”，均不合语境。

　　[答案]B

　　30.—No wonder you caught a cold. You ________ out last night without a coat.

　　—I know how silly I was.

　　A. shouldn't have gone B. mustn't have gone

　　C. couldn't have gone D. mightn't have gone

　　[解析]本题考查“情态动词+have done”。A项意为“本不应该干某事而事实上已干了”;B项表述错误，must 表推测时只用于肯定的陈述句;C项意为“过去不可能干过”;D项意为“过去或许没干”;句意：—难怪你感冒了。你昨天晚上不应该没穿外套就出去。—我知道我有多愚蠢。故可知A项正确。

　　[答案]A

　　31.You ________ not get my support if you do such a thing.

　　A.must B.may

　　C.shall D.need

　　[解析]shall 与第二人称连用，表示警告，允许等语气。

　　[答案]C

　　32.—I just want to know. Please tell me, how much do you make an hour?

　　—If you ________ know, I make $20 an hour.

　　A.will B.shall

　　C.must D.need

　　[解析]must 表示“偏要，一定要”。

　　[答案]C

　　33.—What do you think of the American singer Lady Gaga's performance?

　　—Too crazy, but if she ________ come to China to hold concerts, I would buy tickets for her live show.

　　A. would B. could

　　C. should D. might

　　[解析]本题考查虚拟语气。句意：—你认为美国歌手 Lady Gaga 的表演怎么样?—太疯狂了，但是如果她能到中国来举行演唱会的话，我会买票看她现场演出。由语境可知，此处是 if 引导的虚拟条件句，叙述与将来事实相反，从句用 should do/过去式/were to do，主句用 would/could/should/might do，故C项正确。

　　[答案]C

　　34.Without Sir Tim, the father of the WWW, keeping up with the latest ________ so convenient.

　　A. would be B. wouldn't be

　　C. would have been D. wouldn't have been

　　[解析]本题考查虚拟语气。句意：若没有万维网之父 Tim 先生，跟得上最新信息就不会这么方便了。由语境可知，Without Sir Tim 为含蓄条件句，相当于 If there were not Sir Tim，叙述与现在事实相反，故主句谓语动词用“would/should/could/might+do”，故B项正确。

　　[答案]B

　　35.Look at the trouble I am in! If only I ________ more careful when driving.

　　A. was B. would be

　　C. had been D. should be

　　[解析]本题考查虚拟语气。句意：瞧瞧我的麻烦!要是我开车时小心点儿就好了!if only“但愿……，要是……就好了”，后接从句，从句谓语动词用虚拟语气，叙述与过去事实相反，谓语动词用 had done，故C项正确。

　　[答案]C