D 考查情态动词在语境中的特殊用法。句意：约翰答应医生不再吸烟，从那以后，他再也没有吸过烟。由句意可知空格处表示意愿。
might 用作may的过去式，表示“可以，可能”；should 作情态动词，表示“应当”， 相当于ought to; could可用来代替can说明现在的情况，提出请求、想法、建议等；would 用于过去情况，表示“愿意”， “肯”， “会”等。
John, look at the time. ______ you play the piano at such a late hour?
A. Must
B. Can
C. May
D. Need
A must在此表示特定的语气和态度，意为“偏要，硬要”。
1. can的几个习语
“can but ＋动词原形”表示“只能，大不了”。
“can't but ＋动词原形”表示“不得不”。
“can't help ＋动词ing形式”表示“不得不，禁不住”。
“can't …too…”表示“无论怎样都不为过，越……越……”。
2. must有时表示 “偏要，偏偏”， 也可作名词，意为“必须做的事情”。
3. should可作“竟然、万一”解。 【考点5】shall的三种用法
1．表说话人的意图。在陈述句中主语是第二﹑三人称，表说话者给对方的承诺﹑决心﹑警告、威胁等。
2．征求对方的意见或向对方提出请求时，主语为第一、三人称的疑问句。
3．表示强制。用于法令条约、规章中，意为“必须，应该”。
— Will you read me a story, Mummy?
— OK. You ______ have one if you go to bed as soon as possible. (2011·陕西卷)
A. might
B. must
C. could
D. shall
D shall在此表“许可”。
虚拟语气 【考点1】虚拟条件句的三种基本类型
I ______ through that bitter period without your generous help. (2011·陕西卷)
A. couldn't have gone
B. didn't go
C. wouldn't go
D. hadn't gone
A 句意：没有你慷慨的帮助，我就不可能熬过那段痛苦时期。此句为与过去事实相反的虚拟语气句子。Without your generous help＝if I hadn't had your generous help. 从句用过去完成时，主句则用情态动词＋完成时。couldn't have gone through表“过去不可能度过”。
1. 若与现在事实相反，条件从句的谓语用一般过去时(be通常用were), 主句谓语用“would (should, could, might)＋动词原形”。
2. 若与过去事实相反，条件从句的谓语用过去完成时，主句谓语用“would (should, could, might)＋have＋过去分词”。
3. 若与将来事实相反，条件从句的谓语用一般过去时(be通常用were)或should＋动词原形或were to＋动词原形，主句谓语用“would (should, could, might)＋动词原形”。 【考点2】使用虚拟语气的几种从句
—
Where are the children? The dinner's going to be completely ruined.
— I wish they ______ always late.(2011·北京卷)
A. weren't
B. hadn't been
C. wouldn't be
D. wouldn't have been
A wish后有三种形式的虚拟语气句子。此句根据前一分句where are the children？可知是在问孩子现在在哪里？因此对方才会说我希望他们不要总是迟到。
1. wish后的宾语从句和if only后的句子：表示与现在事实相反的愿望，从句谓语用一般过去时或过去进行时；表示与过去相反的愿望，从句谓语用过去完成时；表示将来没有把握或不太可能实现的愿望，常用“would (could)＋动词原形”。
2. as if / as though引导的方式状语从句或表语从句：表示与现在事实相反，从句谓语用一般过去时或过去进行时；表示与过去事实相反，用过去完成时；表示将来的可能性不大，用“would (could)＋动词原形”。
若从句所说的内容可能为事实，也可用陈述语气。
3. It's (high / about) time后的定语从句：从句谓语通常用一般过去时或“should＋动词原形(should不可省)”。
4. would rather后的宾语从句：通常用一般过去时表示现在或将来的愿望，用过去完成时表示过去的愿望。
5. 一个“坚持”(insist)、两个“命令”(order, command)、三个“建议”(advise, suggest, propose)、四个“要求”(demand, require, request, ask)后的宾语从句：一般用“should＋动词原形(should可省)”。
动词insist, suggest后的宾语从句除可用虚拟语气外，也可用陈述语气，注意区别。
6. It's＋suggested, ordered, required, demanded等表示“建议、要求、命令”的动词的过去分词＋that主语从句：常用“should＋动词原形(should可省)”。
7. “要求、建议、命令”等意义的名词后的表语从句或同位语从句：从句中的动词也用“should＋动词原形(should可省)”。
8. It's＋important / necessary / impossible＋that主语从句：常用“should＋动词原形(should可省)”。 【考点3】虚拟语气的特殊情况 1. 错综时间虚拟条件句
Maybe if I ______ science, and not literature then, I would be able to give you more help. (2011·北京卷)
A. studied
B. would study
C. had studied
D. was studying
C 从句中含有then，可推知此句是一个与过去事实相反的虚拟语气句子，所以用过去完成时。而主句则用了与现在事实相反的would be。句意：也许如果我那时学习了理科而不是文学的话，那么(现在)我就能给你更多的帮助。
所谓错综时间虚拟条件句即条件从句与主句所指时间不一致，如从句指过去，而主句却指现在或将来，此时应根据具体的语境，结合上面提到的三种基本类型对时态作出相应的调整。
【考点3】虚拟语气的特殊情况 2. 含蓄虚拟条件句
I knew my uncle ______ no time. Otherwise he ______ me company to go hiking.
A. did have; would have kept
B. had; had kept
C. has; would have kept
D. had had; had kept
A 本题考查强调和虚拟语气。第一句说的是事实，故不用虚拟语气， did 在此处表示强调；第二空表示对过去事实的虚拟，故用would have kept。
We ______ John's name on the race list yesterday but for his recent injury. (2011·江西卷)
A. will put
B. will have put
C. would put
D. would have put
D but for“要不是因为”。此句表示“要不是因为John最近受伤了，我们将会把他的名字打入竞赛名单里。”受伤这一动作发生在过去，因此该句表与过去事实相反。主句用would have done的形式。
假设情况不用if从句来表示，而是用without, but for, otherwise, or, but等表示一种含蓄条件。表示与现在或将来相反，用“would (should, could, might)＋动词原形”；表示与过去相反用“would (should, could, might)＋have＋过去分词”。
【考点3】虚拟语气的特殊情况 3. 虚拟语气的省略与倒装 ______ in your position, I would go.
A. If I
B. Were I
C. If was I
D. If I am
B 该结构可还原为： If I were in your position。
虚拟条件从句中若有were, should, had时，可将其提到句首，并将if省略。
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第11课时
情态动词和虚拟语气
二
1. You ______ park
here! It's an
emergency
exit.(2010·重庆卷)
A. wouldn't
B. needn't
C. couldn't
D. mustn't
D 考查情态动词。根据语境，这里表示禁止，故选D。
思路点拨
2. — Why didn't you come to Simon's party last night?
— I wanted to, but my mom simply ______ not let me out so late at night. (2011·重庆卷)
A. could
B. might
C. would
D. should
C 考查情态动词。此处would表示一种意愿。
思路点拨 情态动词 【考点1】could与was/were able to的区别
Although the fire in the hotel was very big, they ______ escape from it.
A. can
B. could
C. was able to
D. were able to
D A的时态不对， C选项主谓不一致。could和was / were able to虽都表过去的能力，但后者还表达“付诸了行动”的意思。
could一般只表过去的能力；若表示过去的能力得到了实施，一般用was / were able to, 不用could。
【考点2】表示“可能性”的can, may, must
Liza ______ well not want to go on the trip — she hates traveling.
A. will
B. can
C. must
D. may
D 句意： Liza极有可能不想去旅行——她讨厌旅行。may well not很可能不，表示否定猜测。
It ______ be the postman at the door. It's only six o'clock. (2011·江西卷)
A. mustn't
B. can't
C. won't
D. needn't
B can't “不可能”，表否定推测。根据前后句意思只能用can't。needn't“不必要”；mustn't表“禁止，不许”；won't表将来。
肯定推测一般用must, should, may/might或could(一般不用can), 其中， must的语气最强，意为“肯定”， should次之，意为“很可能，应该”， may/might语气最弱，意为“也许”。否定推测语气不很肯定时常用may/might not或could not, 意为“可能不，也许不”；否定语气较强时则用can't, 意为“根本不可能，想必不会”；用于疑问句表示惊异、怀疑的感情色彩时用can。
【考点3】“情态动词＋have done”的用法 They ______ have arrived at lunchtime but their flight was delayed. (2011·全国新课标卷)
A. will
B. can
C. must
D. should
D should have done表“过去本应该做而未做的”。句意：他们本应该在午饭时候到达的，但是他们的航班误点了。must have done过去一定干过某事，表肯定推测。can have done表过去可能性，“过去本有可能干”。
— I left my handbag on the train, but luckily someone gave it to a railway official.
— How unbelievable to get it back! I mean, someone ______ it. (2011·江苏卷)
A. will have stolen
B. might have stolen
C. should have stolen
D. must have stolen
B might have done表过去很有可能已做某事。而must have done 则表示过去一定有人做过某事。如果被别人偷走了，那么就不可能把东西弄回。will have done 是将来完成时。should have done 过去本该做而未做。
must have done表示对过去事情的肯定推测。 can't / couldn't have done表示对过去所发生的事情所做的否定推测。
may have done表示过去所发生的事情作可能性推测。 might / could have done表示对过去所发生的事情作可能性推测，或者表示本来可以做而事实上未做的事情。 should / ought to have done表示本应该做的事情而事实上未做，含有对对方的责备。
needn't have done表示做了本不应该做的事情。 【考点4】特殊情况
John promised his doctor he ______ not smoke, and he has never smoked ever since.
A. might
B. should
C. could
D. would