2021年高考英语二轮复习考点讲解：情态动词和虚拟语气

榜首部分、神态动词
一、can/could与be able to
1．can/could用来标明“一般才能”；be able to有多
种时态，且用来标明在特定条件下的“详细才能”。

如：My grandma is over seventy，but she can still
read without glasses.
They will be able to tell you the news soon.
He was able to flee Europe before the war broke out.
2．标明答应可用can或could，与may/might含义挨近。

could可用于现在时，仅仅口气愈加宛转、谦让，答复时则一
般要用can而不用could。

—Could I have the television on?
—Yes，you can./No，you can't.
二、may与might
1．标明答应，意为“能够，答应”，用法根本上同can
与could。

如：
May I use your bicycle?
2．标明或许性，意为“或许，或许”。

如：
According to the weather forecast, it may rain tomorrow.
3．may能够放在句首，标明祝福。

如：
May good luck be yours!
三、must与have to
1．must用来标明说话人的片面观点；have to标明客观的需求，着重外界压力，不得已而为之。

如：
He said that they must work hard。

他说他们有必要努力工作。

(片面上要做这件事)
My brother was ill, so I had to call the doctor in the middle of the night.
我弟弟生病了，我只得半夜里把医师请来。

(客观上需求做这件事)
2．标明“不用”，须用don't have to或needn't。

must的否定式标明“制止，必定不行”。

如：
You don't have to tell him about it.
你不用告知他那件事。

You mustn't tell him about it.
你绝不能告知他那件事。

—Must we do it now?
咱们有必要现在做吗？
—No, you needn't.
不，你们不用。

四、shall
1．用于榜首、第三人称的疑问句中，用来寻求对方的定
见或恳求指示。

如：
What shall he do next?
他下一步干什么呢？
2．用于第二、第三人称的陈说句中，标明说话人的志愿，有“指令、正告、许诺、要挟、强制”等意思。

如：
He shall stay in bed.
他有必要躺在床上。

You shall have it back next week.
下周必定还你。

He says he won't go, but I say he shall.
他说他不去，但我说他有必要去。

五、will与would
1．will用于各种人称，标明“毅力、志愿”或“决计”等。

如：
If you will keep your watch half an hour slow, it is hardly surprising that you are late for your appointments.
假如你想要让你的表慢半个小时，你约会时迟到就不足为怪了。

2．will标明习惯性的动作，有“总是，惯于”的含义。

如：An Englishman will usually show you the way in
the street.
英国人一般是会在街上给你指路的。

3．would可标明曩昔重复产生的动作。

如：
On Sundays he would get up early and go fishing.
星期天他总是早上去垂钓。

六、should与ought to
1．should标明“主张”或“劝说”，有“应该”之意。

如：You should learn from each other.
2．ought to标明依据某种责任或必要“应当”做某事。

如：
Everyone ought to obey the traffic regulations.
3．should和ought to也可用来标明估测，意为“想必会……”。

如：
—When can I come for the photos? I need them tomorrow afternoon.
—They should be ready by 1200.
七、神态动词标明估测
1．can用于必定句中标明客观的或许性，意为“有时会”；用于疑问句中能够标明估测，意为“或许”，有时标明一种惊奇的口气；用于否定句中也能够标明估测，can't意为“不或许”，口气很激烈。

It is usually warm in my hometown in March, but it can be rather cold sometimes.
我的家园在三月份一般很温暖，但有时分也会适当冷。

Mr. Bush is on time for everything. How can it be that he was late for the meeting?
布什先生做什么工作都很按时，他怎么或许开会迟到呢？
—Let's visit Tom together, Stephen.
—There's no need to do so. He can't be at home, because I saw him board the flight to Beijing this morning.
——Stephen，咱们一同访问汤姆吧。

——没必要这样做。

他必定不在家，由于今日早晨我看见他登上了飞往北京的航班。

2．may/might用于必定句中能够用来标明不十分必定的估测，意为“有或许”；用于否定句中也能够标明估测，may not意为“或许不”，标明一种不太确认的口气。

The traffic is heavy these days. I might arrive a bit late, so could you save me a place?
这些天交通很繁忙，我或许会来晚一点，请你帮我保存个方位好吗？
3．must标明估测时只能用于必定句中，意为“必定，必定”，标明十分必定的口气(在疑问句中或否定句中要用
can/could)。

—It's the office! So you must know eating is not allowed here.
—Oh, sorry.
——这是办公室！所以你必定知道这儿不许吃东西。

——噢，对不住。

4．should用来标明估测时意为“应该”，即含有“按道理来说应当如此”的意思。

There shouldn't be any difficulty about passing the road test since you have practiced a lot in the driving school.
由于你在驾校练习了这么多，经过路考应该没什么困难。

八、“神态动词＋have done”结构
1．should/ought to＋have done，标明“曩昔本应该做而(实践)没有做的工作”，含有责怪或惋惜的口气，意为“本
应该……”。

其否定方式为“should not/ought not to have ＋done”，标明某种行为本不应产生但实践上产生了。

I shouldn't have watched that movie—it'll give me horrible dreams.
我本不应该看那部电影——它会令我做噩梦。

You ought to have come to the party yesterday, but why didn't you come?
昨日你原本应该参加集会的，但是你为什么不来？
2．must＋have done，用于必定句，标明“曩昔必定做过某事”，标明一种很有掌握的估测。

留意，对曩昔产生的状况的否定估测常用“can't/couldn't＋have done”标明。

—Ye Shiwen won two gold medals in London Olympic Games.
—She must have gone through tough training.——叶诗文在伦敦奥运会获得了两枚金牌。

——她必定遭到严厉的练习。

—Do you know where David is? I couldn't find him anywhere.
—Well. He can't have gone far—his coat's still here.
——你知道大卫在哪里吗？我处处找不到他。

——大卫的上衣还在这儿，因而他必定没走远。

3．needn't＋have done，标明“曩昔没有必要做某事，但实践上做了某事”。

Mark needn't have hurried. After driving at top speed, he arrived half an hour early.
马克本没必要那么匆忙。

他以最快速度开车，成果早到了半个小时。

4．may/might＋have done，标明对曩昔状况的一种不太有掌握的或许性的估测，标明“或许已做了某事……”，否定句标明“或许还没有……”。

Sorry, I'm late. I might have turned off the alarm clock and gone back to sleep again.
对不住，我迟到了。

我或许把闹钟关掉后又睡着了。

5．could＋have done标明“曩昔原本能够做某事，但实践上没有做”；can/could＋have done标明“曩昔或许做了某件事”。

I could have saved the poor rabbit, but I didn't have the right drugs with me at that moment.
我原本能够解救那只不幸的兔子的，但是我其时没有适宜的药品。

第二部分、虚拟口气
一、虚拟口气在虚拟条件句中的用法
虚拟状况从句谓语主句谓语例句
与现在事实相反曩昔式
(be用
were)
would/
should/
could/might
do
If he were here, he might be able to help.
What would you do if you were in his
place？
与曩昔现实相反had done would/
should/
could/might
have done
If I had started a little earlier, I would
have caught the train.
I could have done it better if I had been
more careful.
与将来现实相反曩昔式
were to
do/
should do
would/
should/
could/might
do
If I were to do it, I would do it in a
different way.
I would certainly go if I had time.
1.在详细运用中，条件从句中有时可省掉if而选用倒装结构。

如：
Had it not been for your help, we wouldn't have achieved so much.
2．介词without/but for、连词but、副词otherwise 常用来标明某种假定条件。

如：
I wouldn't have made such rapid progress without your help.
3．有时分从句动作和主句动作产生的时刻不一致，这时谓语动词的方式要依据各自的时刻来调整。

如：
If the weather had been more favourable, the crops would be growing still better.
二、“should＋动词原形”标明的虚拟口气
这一类型常见词有“一坚持(insist)、二指令(order, command)、三主张(advise, suggest, propose)、四要求(request, require, demand, desire)”。

以上词及其派生名词所接的名词性从句都运用“(should＋)动词原形”的虚拟口气。

①Jane's pale face suggested that she was ill, and her mother suggested that she(should) have a medical examination.
简苍白的脸色标明她病了，她母亲主张她去查看身体。

②She insisted that the man had stolen her car and that he(should) be sent to prison.
她坚持说那个男人偷了她的车，并坚决要求他坐牢。

三、特别句式中的虚拟口气
If only/It's (high) time (that)．..
wish/would rather/as if等固定句式要求用相应的虚拟口气表达方式。

①I wish I could fly.
真期望我能飞。

②I would rather you came tomorrow.
我甘愿你明日来。

③If only I had taken your advice!
要是遵从了你的主张该多好啊！
高频考点一、调查神态动词
例1．（2018·北京卷）In today’s information age, the loss of data _________ cause serious problems for
a company.
1.need B. should C. can D. must
【答案】C
【解析】调查神态动词。

句意：在今日的信息时代，数
据的丢掉有时会对一个公司形成严峻的问题。

数据丢掉
形成严峻问题是客观上会产生的状况，即“客观或许
性”，故该空运用神态动词can。

C选项正确。

其他神态
动词均没有该用法。

need需求；should应该，居然；
must有必要，必定。

【变式探求】—Can’t you stay a little longer?
—It’s getting late. I reall y _____go now, My
daughter is home alone.
A .may
B .can
C . must
D .dare
【答案】C
【解析】句意：——你不能再多待会儿吗?——很晚了，
我有必要得走了。

我女儿一个人在家。

A. may或许，能
够，或许；B. can能，会；C. must有必要，必定要，
必定会；D. dare敢，竟敢。

结合句意，故选C。

【变式探求】________ I have a word with you? It won’t take long.
a.CanB. Must
C. Shall
D. Should
【答案】A
【解析】本题调查的是神态动词根本含义剖析。

Can
能够，或许；must有必要，必定；非得；shall即
将；should应该；句意：我能够和你谈谈吗？不会
花许多时刻的。

依据句意可知本题运用can I…？
标明问询对方是否答应。

如：Can I use your
dictionary?我能够运用你的字典吗？故A正确。

高频考点二、调查神态动词的用法
例2. （2018·天津卷） I can't find my purse.
I___________ it in the supermarket yesterday, but I'm not sure.
A. should leave
B. must have left
C. might leave
D. could have left
【答案】D
【解析】调查神态动词表估测。

句意：我不能找到
我的钱包了，昨日我有或许把它落到超市了，但我
不确认。

依据句中时刻状语yesterday可知，是对
曩昔工作的估测，故用神态动词+ have done，再依据后句but I’m not sure.可知，此估测为不能必
定的估测，故用神态动词could，标明“或许”。

故选D。

【变式探求】（2017•天津）My room is a mess, but I __________clean it before I go out tonight. I can do it in the morning.
A. daren’t
B. shouldn’t
C. needn’t
D. mustn’t
【答案】C
【解析】句意：我的房间很乱，但是在今晚我出去之前不需求清扫，我能够明日早晨再清扫。

A.不敢；
B.不应该；C不需求；D.不许。

依据句意，故选C。

【变式探求】Why didn't you tell me about your trouble last week？If you ________(tell)me，I could have helped.
【答案】had told
【解析】句意：上个星期你为什么不告知我你的麻
烦事？假如你告知我了，我就能帮你。

依据句意和
相关信息判别，条件句标明与曩昔现实相反的假定，此刻从句用曩昔完成时，主句谓语用“神态动词＋
have done”方式。

【变式探求】I ______ have worried before I
came to the new school, for my classmates
here are very friendly to me.
i.mightn’tB. mustn’tC.
needn’tD. couldn’t
【答案】C
【解析】句意：我来新学校之前本没有必要忧虑，由于在这儿我的同学对我十分友爱。

needn’t have done本没有必要做某事，标明实践上现已做了某事。

依据句意可知选C。

高频考点三、调查虚拟口气
例3．(2019·天津卷)The workers were not better organized, otherwise they ________ the task in half the time.
A．accomplished B．had accomplished
C．would accomplish D．would have accomplished 【答案】D
【解析】调查虚拟口气。

句意：工人们没有被安排好，不然的话他们会用那一半的时刻完成任务的。

此处otherwise
表达了一种宛转虚拟；otherwise前的内容所述的是曩昔的现实，适当于if引导的条件状语从句“If the workers had been better organized”，因而后半部分运用“主语＋would have done sth.”的结构。

故选D。

【触类旁通】【2018·江苏】
It’s strange that he _______
have taken the books without the owner’s permi ssion.
A. would
B. should
C. could
D. might
【答案】B
【解析】调查虚拟口气。

句意：真古怪，他居然没有主
人的答应就拿走了这些书。

在句型”It is
important/necessary/strange/impossible/natural that...”中，其间由that引导的主语从句一般用“should+动词原形”这样的虚拟口气，其间的should能够省掉。

故选B。

【变式探求】（2017·北京）If the new safety
system _______ to use, the accident would never have happened.
A. had been put
B. were put
C. should be put
D. would be put
【答案】A
【解析】句意：假如这个新的安全体系被投入运用过的话，这个事端就不会产生了。

依据主句确认是对曩昔状况的虚拟，所以从句谓语用had done方式，此外依据句意可知是被迫，用被迫语态，故A项是正确的。

【变式探求】________(have)the governments and scientists not worked together，AIDSrelated deaths would not have fallen since their highest in 2005.【答案】Had
【解析】句意：假如政府和科学家不共同努力，与艾滋病相关的逝世就不会从2005年的最高点下降。

这是一个省掉了隶属连词if的虚拟口气句，运用了倒装句式。

依据主句的would not have fallen可知，这儿是标明曩昔的虚拟口气，所以用had。

【变式探求】Without his wartime experiences, Hemingway____ his famous novel A Farewell to Arms.
A.didn’t write
B. hadn’t written
C. wouldn’t write
D. wouldn’t have written
【答案】D
【解析】句意：没有他战时的阅历，海明威就不或许写
出闻名的小说永别了兵器。

依据without his wartime experience没有战时的阅历，可知标明关于曩昔的否定猜想，故主句用would have done，因而选D项。

1．(2019·天津卷)The workers were not better organized, otherwise they ________ the task in half
the time.
A．accomplished B．had accomplished
C．would accomplish D．would have accomplished
【答案】D
【解析】调查虚拟口气。

句意：工人们没有被安排好，
不然的话他们会用那一半的时刻完成任务的。

此处otherwise
表达了一种宛转虚拟；otherwise前的内容所述的是曩昔的现实，适当于if引导的条件状语从句“If the workers had been better organized”，因而后半部分运用“主语＋would have done sth.”的结构。

故选D。

2．(2019·江苏卷)What a pity! You missed the sightseeing, or we ________ a good time together. A．had B．will have
C．would have had D．had had
【答案】C
【解析】调查虚拟口气。

句意：多么惋惜！你错过了这次旅游。

不然，咱们就能够一同度过一段愉快的韶光。

依据关键词or可知，这儿标明与曩昔的现实相反，谓语动词运用would/could/should/might＋have done。

1.【2018·江苏】 There is a good social life in the village, and I wish I _______ a second chance to become more involved.
A. had
B. will have
C. would have had
D. have had
【答案】A
【解析】调查虚拟口气。

句意：在这个村里有很好的社交生活，而且我期望我再有机会去更多的参加。

本题调查
wish引导的宾语从句，标明与现在现实相反的希望，所以从
句用一般曩昔时。

故选A。

2.【2018·江苏】It’s strange that he _______ have taken the books without the owner’s permi ssion.
A. would
B. should
C. could
D. might
【答案】B
【解析】调查虚拟口气。

句意：真古怪，他居然没有主
人的答应就拿走了这些书。

在句型”It is
important/necessary/strange/impossible/natural that...”中，其间由that引导的主语从句一般用“should+动词原形”这样的虚拟口气，其间的should能够省掉。

故选B。

3.（2018·天津卷） I can't find my purse.
I___________ it in the supermarket yesterday, but I'm not sure.
A. should leave
B. must have left
C. might leave
D. could have left
【答案】D
【解析】调查神态动词表估测。

句意：我不能找到我的
钱包了，昨日我有或许把它落到超市了，但我不确认。

依据句中时刻状语yesterday可知，是对曩昔工作的估测，故用神态动词+ have done，再依据后句but I’m not sure.可知，此
估测为不能必定的估测，故用神态动词could，标明“或许”。

故选D。

4.（2018·北京卷）In today’s information age,
the loss of data _________ cause serious problems for
a company.
A. need
B. should
C. can
D. must
【答案】C
【解析】调查神态动词。

句意：在今日的信息时代，数
据的丢掉有时会对一个公司形成严峻的问题。

数据丢掉形成严峻问题是客观上会产生的状况，即“客观或许性”，故该空运用神态动词can。

C选项正确。

其他神态动词均没有该用法。

need需求；should应该，居然；must有必要，必定。

5.（2018·北京卷）They might have found a better hotel if they _________ a few more kilometers.
A. drove
B. would drive
C. were to drive
D. had driven
【答案】D
【解析】调查虚拟口气。

句意：假如他们多开几公里的话，他们或许会找到一个更好的旅馆。

由“they might have found a better hotel”可知，该句是标明对曩昔的虚拟。

if ____ a few more kilometers是条件句部分，标明对曩昔的
虚拟，条件句部分要用曩昔完成时态，故D选项正确。

1．（2017·北京）Samuel, the tallest boy in our class, ______ easily reach the books on the top shelf.
A. must
B. should
C. can
D. need
【答案】C
【解析】A. must 有必要 B. should 应该 C. can 能 D. need 需求。

句意:Samuel，我班最高的男生，能很轻松地够着书架顶上的书，此处需求一个标明才能的词，故用can，答案
为C。

2．（2017•天津）My room is a mess, but I
__________clean it before I go out tonight. I can do
it in the morning.
A. daren’t
B. shouldn’t
C. needn’t
D. mustn’t 【答案】C
【解析】句意：我的房间很乱，但是在今晚我出去之前
不需求清扫，我能够明日早晨再清扫。

A.不敢；B.不应该；C
不需求；D.不许。

依据句意，故选C。

3．（2017•江苏） _______ not for the support of the teachers, the student could not overcome her difficulty.
A. It were
B. Were it
C. It was
D. Was it
【答案】B
【解析】调查虚拟口气和倒装。

虚拟口气中，be动词统
一用were；虚拟口气的省掉方式主要是把if省掉，一起把were/should/had提早，即Were /Should/ Had I...，故选B。

句意：要不是教师们的支撑，该生是无法战胜她自己的困难的。

4．(2017·江苏卷) ____________ not for the
support of the teachers, the student could not overcome her difficulty.
A. It were
B. Were it
C. It was
D. Was it
【答案】B
【解析】调查虚拟口气的省掉。

虚拟口气中，be动词统
一用were；虚拟口气的省掉方式主要是把if省掉，一起把were/should/had提早，即Were /Should/ Had I...，故选B。

5．（2017•江苏） _______ not for the support of the teachers, the student could not overcome her difficulty.
A. It were
B. Were it
C. It was
D. Was it
【答案】B
【解析】调查虚拟口气和倒装。

虚拟口气中，be动词统
一用were；虚拟口气的省掉方式主要是把if省掉，一起把were/should/had提早，即Were /Should/ Had I...，故选B。

句意：要不是教师们的支撑，该生是无法战胜她自己的困难的。

6．（2017·北京）If the new safety system _______ to use, the accident would never have happened.
A. had been put
B. were put
C. should be put
D. would be put
【答案】A
【解析】句意：假如这个新的安全体系被投入运用过的话，这个事端就不会产生了。

依据主句确认是对曩昔状况的虚拟，所以从句谓语用had done方式，此外依据句意可知是被迫，用被迫语态，故A项是正确的。

1．(2016·浙江，15)________(have)the governments and scientists not worked together，AIDSrelated deaths would not have fallen since their highest in 2005.
【答案】Had
【解析】句意：假如政府和科学家不共同努力，与艾滋
病相关的逝世就不会从2005年的最高点下降。

这是一个省掉了隶属连词if的虚拟口气句，运用了倒装句式。

依据主句的would not have fallen可知，这儿是标明曩昔的虚拟口气，所以用had。

2．(2016·浙江，17)George can't ________(go)too far.His coffee is still warm.
【答案】have gone
【解析】句意：乔治不或许走得太远了。

他的咖啡仍然
是温的。

can't have done是对曩昔的否定估测。

3．(2016·北京，34)Why didn't you tell me about your trouble last week？If you ________(tell)me，I could have helped.
【答案】had told
【解析】句意：上个星期你为什么不告知我你的麻烦事？假如你告知我了，我就能帮你。

依据句意和相关信息判别，条件句标明与曩昔现实相反的假定，此刻从句用曩昔完成时，主句谓语用“神态动词＋have done”方式。