英语语法词法情态动词知识点学习笔记思维导图

英语语法词法情态动词知识点学习笔记，包括过去的能力，建议和忠告，意愿意图与执意。过去的习惯，情态动词的否定等等内容。帮助大家学好英语语法～

英语语法词法情态动词知识点学习笔记思维导图

情态动词全家福

情态动词

现在式

can

may

must

shall

will

过去式

could

might

------

should

would

情态动词短语

be able to

be allowed to

have(got) to

be supposed to/ought to

be going to

推测用法（一）：现在推测（情态动词+一般式）

对现在的肯定推测

must表示“推测”及其他含义

表肯定推测

例句

A:Why isn't John in class? B:He must be sick.

You've been traveling all day.You must be tired.

It must be hot in there with no air-conditioning. 那里没有空调，一定很热。

表示“责任”或“义务”，“必须”

强烈的必须

例句

You must wear a seat belt while driving. 开车时必须系安全带

说话人认为某事重要，必须完成的“义务”

You must concentrate on one thing at a time. 做事时你必须一心一意。

含义更弱的“义务”，描述说话人自身的情况

I must remember to feed the cat later.

I must try harder next time.

口语中，语气更弱的义务，用来谈未来的安排

You must come to see us one of these days. 你这几天得来看看我们啊。

We must get together for lunch sometime. 我们得找个时间聚一聚，吃个午饭。

have to用法

与must一致，可“推测”或表“必须”

Look at that house!Those people have to have a lot of money.

与must的区别

在时态表达上，must只能谈现在或将来.而have to 则有各种时态变化。

例句

When I was in school,we had to wear school uniform.

A:Do we really have to go to this meeting? B:Yes,and we will have to present our report.

如果是来自外界不可控的行为，则要用have to

Excuse me,but I have to sneeze. 对不起，我要打喷嚏。

口语中，have got to更常见

They've got to try harder next time.

You've got to be joking.

注意，have got to没有时态的变化。

简单比较“推测”和“必须”

表示“推测”时，must不能表示将来，而只能表示对现在的推测和对过去的推测。若是 表示对现在的推测，其谓语形式是“must+一般式”，即must do;或“must+进行式”，即must be doing。若是表示对过去的推测，其谓语形式是“must+完成式”,即must have done.

表示“必须”时，must不能谈过去的事件，而只能谈现在和将来的事情。其谓语形式都是“must+一般式” ，即must do。不能用“must+进行式或完成式”，即must be doing或must have done中的must一定不会译为“必须”，而只能表示推测。must表示“必须”的意义时是没有过去时态的，要表示 “过去必须”，则要借用had to来表达。

在表示“必须”时，must后面的谓语动词一般是表示动作的，具体来说，就是现在的动作 或将来的动作，不会是表示状态。在表示"推测"时，must后面的谓语动词可以是动作， 也可以是状态。

He must be dead. 他一定是死了。 谓语动词be表示状态。

其他表示推测的情态动词

may,might,could等。

例句：

He is sick.

He must be sick

90%

He may be sick.

50%

He could/might be sick

25%

对现在的否定推测

A:The restaurant is always empty. B:It isn't good.

It can't/couldn't be good.

90%

It may not be good

50%

It might not be good.

25%

注意

must推测不能用作否定中。

can表示推测不能用在肯定中

You must be joking.You couldn't be serious.

在肯定推测中，could的肯定程度很低，但在否定推测时，couldn't则表示十分确信，译为“不可能”

对现在推测的其他情态动词

will和should也可以用来表示对现在的推测，其肯定程度等同于must.

例句

Ring his home number.He'll be at home now. =He must be at home now.

It's no use asking Tom;he won't know. 我肯定他不知道。。。

A:This should be State Street up here. B:It's not.I think you shoud have turned left at the last intersection. A:这应该就是国家大街了。 B:不是。你应该在上一个十字路口左转。

推测用法（二）：将来推测（情态动词+一般式）

除了must,情态动词如will,should,may,might和could都可以表示对将来的预测

例句

It will rain tomorrow.

It should rain tomorrow.

It may rain tomorrow.

It might/could rain tomorrow.

A:Think it'll rain tomorrow?I am sure it won't. B:But according to the weather report,it will rain tomorrow.

should表示程度较大的肯定

He should have plenty of time to get to the station.

The job should be finished by next Monday.

may表示约50%肯定的推测

Tomorrow's computers may have something for your nose to enjoy.

This bridge may collapse in an earthquake.

could/might表示很不肯定

There might/could be a strike next week.

I might be given a new job soon.

否定的can't/couldn't要比may not/might not的否定语气强烈

We may not/might not go camping this summer. 今年夏天我们可能不去野营。

We can't/couldn't go camping this summer. 今年夏天我们不可能去野营。

期望不发生的，不用should

Let's not go to the movie.It could be bad.

Lets go to the movie.The film should be really good.

There should be another disaster shortly.

There could be another disaster shortly.

推测用法（三）：过去推测（情态动词+完成式）

对过去行为发生的可能性的推测。

"must／may ／might ＋现在完成式"表示对过去行为是否发生的可能性程度不同的肯定推测。

"must＋现在完成式"这一用法是指说话人对过去所发生的事情的肯定推断，含有逻辑上的必然性。

例句

He must have gone to the clinic． 他一定是去医务室了。

They started early this morning；they must have arrived by now． 他们一大早就启程了，现在一定到了。

"may ＋现在完成式"表示从现在看来过去可能发生某事。可译为"曾经"、"一度"、"也许"等。

He may have missed the train．他可能没有赶上火车。

"might ＋现在完成式"表示"可能、也许、已经"，但事实上并未如此。

I might have come to a wrong conclusion． 我可能得出了错误的结论。

表示对过去行为可能性的否定推测。

"could ／can not＋现在完成式"表示以现在的眼光看来， 过去不可能发生的事。可译为"不可能或不至于"。

例句

They couldn't have left so soon． 他们不可能那么早就走了。

They can't have missed the way．（They've been to the zoo before．） 他们不可能迷路。（暗含他们以前去过动物园。）

I can't have seen him． 我不可能见过他。

"may not ＋现在完成式"表示"不一定发生过、未必发生过"等。

"might not ＋现在完成式"表示"不一定就、也可能不、未免有点不"。

表示说话人的语气。

表示委婉批评

"could ＋现在完成式"含有埋怨或训斥的口气。

例句

I could have lent you the money．Why didn't you ask me？ 我本来可以把钱借给你的。你为什么没有向我借呢？

might ＋现在完成式

例句

You might at least have answered my letter．你至少可以回我一封信嘛。

You might have been more careful．你本可以再细心一些。

表示惊奇或怀疑

"could ／can ＋现在完成式"常用在疑问句中

例句

Where（can）could they have gone？他们可能到哪里去了呢？

How could they have forgotten such an important meeting？他们怎么能忘记这么重要的会议呢？

表示说话人认为过去的行为应该或不应该发生。

"should ／ought to ＋现在完成式"表示说话人认为该做而实际未做的事

例句

They ought to have done that but they didn't．他们本应该这样做。

He should have told me the news earlier．他本应该早些告诉我这消息。

"should not／ought not to ＋现在完成式"表示过去做了不该做的事。

例句

You oughtn't to have done that．你这么做是不应当的。

You should not have gone up to college so soon．（But you did．）你本不应该这么早就上大学的。

They shouldn't have come．他们本不应该来。

表示不必要性。表示说话人对过去已做的事情持否定态度， 或认为此事根本没必要做。常用句式为"needn't ＋现在完成式"。

例句

I needn't have hurried．我大可不必这么急。

The war needn't have cost mankind so many lives．-It needn't have happened． 在那场战争中本来不必有那么多人丧生，不仅如此，本来就是一场不必要的战争。

表假设。

"wouldn't＋现在完成式"表示与事实相反的动作，实际上已经做了，但假设没有做。可译为"就不会、决不会"等

If not for these armed forces，the situation in China would never have been what it is today！ 要是没有这些军队，中国绝无今天的局面！

推测用法（四）：情态动词+（完成）进行式

直接上例句

The plane should be landing now. 飞机现在肯定在降落。

They can't be having dinner right now. 他们现在不可能还在吃晚饭。

You must have been dreaming. 你刚才一定是一直在做梦。

持续的状态

You can't/couldn't have been swimming all day. 你不可能一整天都一直在游泳。

“情态动词+完成进行式”也可以用在虚拟语气中

You shouldn't have been following him so closely;you should have kept your distance. 你本不该一直跟着他那么近，你应该和他保持一定的距离。

基本用法（一）：现在或将来的能力

这一节比较简单，反复介绍的是can这个单词，主要的核心意义为“潜在可能性”

例句

I don't know how she knows,but Mom can always detect when I'm lying.

The theater can seat 10,000 people.

A fish can't walk,but it can swim.

John is strong.He can lift that heavy box.

基本用法（二）：现实“可能”与理论“可能”

与说话当时的现状有联系的，则是“实际上的可能”

与说话当时现状无关的，则是“理论上的可能”

can用来讨论理论上的可能。

在肯定句中，不能谈“实际上的可能”。

例句

Even experienced teachers can make mistakes. 即使是再有经验的老师也有可能犯错误。

Winter here can be really cold. 这里的冬天会非常冷。

You can be very critical sometimes. 你这人有时候还真的是很挑剔啊。

在否定句中，can't主要谈“实际上的可能”，相当于must的否定形式

例句

This must be the way to the post office. 这一定是去邮局的路。

This can't be the way to the post office. 这不可能是去邮局的路。

Even experienced teachers can't make mistakes.

在疑问句中，can既可以表示“理论上的可能”也可以表示“具体的可能”

例句

Can measles be quite dangerous? 麻疹有可能很危险吗？

理论上的可能

A:Do you think he can be right? B:He can hardly be right.

具体的可能

Someone is knocking at the door.Who can it be?

具体的可能

基本用法（三）：过去的能力

can/could表示“能力”时，二者均表示“潜能”或者说“一般能力”

can表示将来或现在的一般能力

could表示过去的一般能力

could不表示“过去具体的能力”；was/were able to既可以表示“过去的一般能力”，也可以表示“过去具体的能力”

I could repair the old car. 我过去是能够修理旧汽车的。

I was able to repair the old car. 我终于把那辆旧汽车修理好了。

could have done用来表示“过去的可能”

在否定句中个，couldn't和wasn't/weren't able to没有区别，即couldn't可以谈过去具体的能力，表示在过去的某一个特定场所“未能”完成某事。

例句

Today I can go to Disneyland.

Today I am able to go to Disneyland.

Yesterday I could go to Hong Kong Disneyland.

Yesterday I was able to go to Hong Kong Disneyland.

去了

Yesterday I could have gone to Hong Kong Disneyland.

我昨天本来可以去，但结果没有去成。虚拟

表示过去“潜能”

He could/was able to pull down a bull and acknowledged as a man with superman strength. 他曾能够拉倒一头牛，被公认为是具有神力的人。

I could/was able to recite several poems when I was 3 years of age.

In those days few workers could support their families. 那时很少有工人能够养家糊口。

表示过去的“实际行动”（均不能用could）

They were able to get tickets to the Rolling Stones concert last week. 上周他们搞到了滚石乐队的演唱会门票。

The two boys tried many ways to catch that sly fox and were able to do so at last. 两个孩子试用了多种方法抓那只狡猾的狐狸，最后终于成功了。

He didn't agree with me at first but I was able to persuade him. 起初他并不同意我的意见，但最后我成功地说服了他。

I ran after the bus yesterday,but wasn't able to/couldn't catch it.

基本用法（四）：许可

重点

1、可以用的情态动词有may,might,can和could，但多用can或be able to do表示许可。

2、表示“许可”一般用陈述句

3、肯定的陈述句表示允许某人做某事；否定的陈述则表示不允许某人做某事。

肯定句---给予许可

例句

We can borrow these books from the library. =We are allowed to borrow these books from the library.

You need to get a license before you can drive a car in this country. =You need to get a license before you are allowed to drive a car in this country.

I can leave the office as soon as I have finished. =I am allowed to leave the office as soon as I have finished.

A:May I turn on the TV? B:Yes,of course you may.

口语中，can比较常用，may表示“许可”会用在非常正式的文体中。

You may only register for two classes. 你只能报两门课。

can表示“许可”和“能力”的辨别

can表示能力时，不宜和将来的时间状语连用

例句

You can use my car tomorrow.

表示许可

若有表示将来的时间状语，要说will be able to do

例句

You can pass your driving test next time you take it.

You will be able to pass your driving test next time you take it.

否定句---拒绝许可，甚至禁止

例句

A:May I borrow your car? B:No,I'm afraid you may not.

You may not smoke in here. =You are not allowed to smoke in here.

You can't take your camera into the museum.

还可以用must not表示强烈的拒绝许可--禁止

Students must not take the test papers out of the classroom.

could一般不用来表示现在的许可，而表示过去的许可

表示过去的一般许可，could与was/were allowed to do可以互换。

例句

I could/was allowed to read what I liked when I was a child. 我小的时候爱看什么书，就看什么书。

若表示过去允许进行某项活动时，要用was/were allowed to do

例句

Yesterday evening,Peter was allowed to watch TV for an hour.

Yesterday evening,Peter could watch TV for an hour.

基本用法（五）：建议和忠告

could表示建议

could表示“建议”时，并不表示过去。

例句

A:What shall we do this evening? B:We could go to the cinema.

It is a nice day.We could go for a walk.

Shall I...?Shall we...?

shall用于第一人称的一般疑问句中，表示征求对方的“建议”

例句

Shall I open the window? =Would you like me to open the window?

Shall we leave at two.

may(just) as well,might(just) as well

这组情态动词表示“建议换另一种方式做某事”，可译成“倒不如”，“不妨”

例句

A:I'll go on Monday by train. B:You might just as well wait till Wednesday and go by plane.

We may as well stay here tonight. 我们今晚不如在这过夜。

may/might as well还有一种多少有些勉强或讥讽的意味。

例句

It's no use waiting here.We might as well start walking. 在这里干等没用，我们还不如开始不行回去。

You might as well tell the truth(as continue to tell lies). (与其继续撒谎)你不妨还是实话实说了吧。

should和ought to表示忠告

例句

You should brush your teeth twice a day. 你应该每天刷牙两次。

We should call them before we go there.

should往往也含有“责任”和“义务”的含义

例句

Drivers should obey the speed limit.

比must的责任意味要轻一点

Why should I do what everyone else does? 为什么我非得跟其他人一样啊？

上述例句也可以用ought to，不过更多的出现在口语中。

should表示“忠告”与could表示“建议”比较

should表示强烈的，明确的忠告；could表示建议某事的可能性

例句

A:I need to get to the airport. B1:You should take the airport bus.It's cheaper than a taxi. B2:Well,you could take the airport bus.Or you could take a taxi.Maybe Clint could take you.He has a car.

had better表示“忠告”

后接动词原型

had better在表示忠告时，有时会暗含“如果不这么做，就会有不良后果”的意思

例句

We had better study harder,or we'll probably fail in the exam.

You had better return the book to the library.

基本用法（六）：意愿、意图与执意

预测和意愿

例句

A:The phone's ringing. B1:That'll be for me. B2:I'll get it.

意图

例句

I will borrow some money and buy a car.

I will make dinner for tomorrow night. 明晚我来做晚饭。---承诺

I'll call the police if you don't leave. --威胁

执意

坚持“意图”而不愿改变

此时肯定的will相当于insist 某人坚持要做某事； 否定的won't表示坚持不愿意做某事或禁止做某事，won't相当于refuse

例句

If they will pay in cash,we have to accept it although it'll cause trouble to both sides. 如果他们非要坚持用现金支付，那我们也没办法，只好接受了，尽管这会给双方都造成麻烦。

If they will not accept a check,we shall have to pay cash,though it would be much trouble for both sides.

A:I won't do it.我不做。 B:Yes,you will.没门，你一定得做。

注意，当will表示“执意”这种强烈的感情色彩时，一方面不要缩写成'll； 另一方面，will要重读。

will表示执意对应于过去，则用would

例句

We all tried to stop him smoking in bed but he would do it.

基本用法（七）：请求

请求对方允许我们做某事

Can/Could I...?

May/Might I...?

注意：

May I...?和Could I...?表示较正式、很礼貌的提出请求。

例句

May I have your name,please? 请问您怎么称呼？

Could I have two tickets,please? 请给我两张票好吗？

Can I...?是非正式的请求允许，一般用于熟人或朋友之间的对话

例句

Can I use your pen?

A:Hi,Jenny.Can I join you? B:Sure,Michael.Please sit down.

Might I...?显得过于正式和客气，一般很少用。

请求对方为我们做某事

Can/Could you...?

Will/Would you...?

注意

Would you...?和Could you...?都是用来表示很客气地请求对方

例句

Would you please open this door?

Could you put out your cigarette,please? 请你把烟熄了，好吗？

Will you...?不如Would you...?客气

Can you...?常用于非正式场合、熟人之间

Can you pass me the salt,Mom?

表示请求时，越不肯定或犹豫，就越显得礼貌

一般疑问句

常见句型

Could you do...?

Could you please do...?

Could you possibly do...?

Would you do...?

Would you please do...?

Would you kindly do...?

Would you mind doing...?

Would you be good/kind enough to do...?

Would you be so kind as to do...?

Do you think I could...?

Do you think you could/would do/would mind doing...?

例句

Could you bundle these clothes off to my sister? 把这些衣服寄给我姐姐好 吗 ?

Could you please help me, Constable? 警察,您能帮助我 吗 ?

Sorry, I didn't catch what you said. Could you please say it again? 对不起, 我没听清楚你说的话,请你再讲一遍好 吗 ?

Could you possibly change three dimes into six nickels? 你能把三枚十分的硬币换成六枚五分钱的 吗 ?

Could you possibly ask the official to send me one? 请您让主管人员寄给我一份好 吗 ?

Would you come into the bar and have a drink with me? 你愿意进酒吧和我喝一杯 吗 ?

Would you be good enough to move a bit to the right? 请你往右边移一点好 吗 ?

陈述句

常见句型

I wonder if I could do...

I wondered if I could do...

I was wondering if I could do...

I wonder if you could/would do/would mind doing...

I wondered if you could/would do/would mind doing...

I was wondering if you could/would do/would mind doing...

例句

I wonder if we could make It'some other time. 我想知道我们可否把它安排在其他时间.

I wondered if you could buy me some pencils? 我不知道你是否能替我买铅笔?

I was wondering if you could teII me what skin - care regimen you use. 我很好奇你能告诉我你用什么护肤品吗?

I was wondering if I could turn on the TV now? 我不知道我是否可以现在打开电视?

基本用法（八）：过去习惯

would有时表示过去反复发生或习惯性的动作

例句

When I was a child,my mother would read me a story at night before bed. 小时候，晚上睡觉前妈妈常常会给我讲故事。

When I was a child,I would take a flashlight to bed with me so that I could read comic books without my parents' knowing about it. 小时候，我常常会拿着手电筒在床上看连环画，这样爸妈就不会发觉了。

用would表示过去习惯或习惯性动作时， 还可以是某人一贯的行为。这时，往往 用来批评。要重读！

例句

We all tried to stop him smoking in bed but he would do it. 我们都试图不让他在床上抽烟，可他每次偏偏这么做。

A:Bill objected.当时比尔反对。 B:He would!他老是反对！

与used to区别

used to可以表示过去重复的动作，也能指过去存在的状态，有“现在不再”的含义

would常用来表示过去重复的动作，不表示过去的状态。

例句：

My own mother uesed to be very busy the whold day.

过去存在的状态---be very busy

Illiteracy is still a problem in my country,but it used to be much worse. 文盲在我们国家仍然是一个问题，但在过去更为严重。

基本用法（九）：should的特殊用法

should表示“竟然”

用在下列形容词后面的从句中的should，带有一种很“惊奇”的感情色彩，含有“竟然”的意思。

It is/was absurb,amazing,annoying,funny,ludicrous,odd,ridiculous,strange,surprising,unthinkable that...等

例句

It is ridiculous that we should be short of water in a country where it is always raining. 在经常下雨的国家里，我们竟然会缺少，这简直是荒谬！

It is unthinkable that he should be so careless.

It's strange that you should be staying in the same hotel.

It's odd that you and I should have the same name.

此时，从句中也可以用现在时态或过去时态

I don't know why he should think that I did it. 我真不知道他凭什么竟然会认为这件事是我干的。

I see no reason why you should interfere in their quarrel. 我真不明白你有什么理由竟然会介入他们的争吵。

Why should anyone bother to risk losing his treasure to help a stranger? 为什么竟然会有人冒着失去自己财产的危险而去帮助一个陌生人呢？

should表示“万一”

should常常用在lest，for fear that和in case引导的从句中，表示“万一”

例句

I've brought my umbrella in case it should rain. 我把伞带着，以防万一下雨。

=I've brought my umbrella in case it rains.

基本用法（十）：shall的特殊用法

用于第一人称的疑问句中：Shall I/we...?

主动提供帮助

例句

Shall I go and fetch it? =Would you like me to go and fetch it?

Shall I open the window? =Would you like me to open the window?

主动提供建议

例句

Shall we meet at the theater?

Let's meet at the theater,shall we?

Shall we leave at two?

What shall we do this evening?Shall we go to the theater?

表示请求给予提示

例句

How shall I cook it?

Where shall we put this?

用于第三人称的疑问句中

例句

A man wants to see you,sir.Shall he wait outside? =Would you like him to wait outside?

Shell he come with us？ =Would you like him to come with us?

用于第二、三人称的陈述句中

表示命令

用在非常正式的场合。

例句

It has been announced that candidates shall remain in their seats until all the papers have been collected. 已经宣布，在所有试卷全部收齐之后，考生方能离开自己的座位。

Each competitor shall wear a number. 每位参赛选手必须佩戴号码。

表示说话人的许诺

例句

You shall have the money back next week. =I promise you will have the money back next week.

If he passes the examination he shall have a bicycle.

表示说话人强烈的意愿、甚至威胁

例句

They shall do as they are told. 他们一定要按照吩咐他们的去做。

He shall be punished if he disobeys.

基本用法（十一）：may的特殊用法

may...but表示让步

例句

We may have our differences from time to time,but basically we trust one another's judgement. =We admit that we have our differences,but basically we trust one another's judgement. =Although we have our differences,basically we trust on another's judgement. 尽管我们常常有分歧，但是我们基本上还是信任彼此的判断。

You may have good reasons,but that doesn't make it legal.

She may be the boss,but that is no excuse for shouting like that.

You may be older than me,but that doesn't mean you're cleverer.

I may be small,but I am influential. 尽管我身材矮小，但我是很有影响力的。

基于may可以表示让步，因此它常常用于各种结构的让步状语从句中

例句

But however amazed our descendants may be at how far from Utopia we were,they will look just like us. 但是不管我们的后代对我们离乌托邦之遥远感动多么吃惊，他们的长相将和我们一样。

When a new movement in art attains a certain fashion, it is advisable to find out what its advocates are aiming at, for, however farfetched and unreasonable their principles may seem today, it is possible that in years to come they may be regarded as normal. 当艺术领域的一个新运动发展成某种流行时尚时，最好应该弄清这场运动倡导者的真正意图， 因为，不管他们的原则在今天看来多么牵强无理，很可能多年以后他们的理论会被视为正常。

Try as he will,no man breaks wholly loose from his first love,no matter who she be...We've only one virginity to lose and where we lost it there our hearts will be. no matter who she be=no matter who she might be 不管怎么样，没有一个男人能够完完全全地忘却自己的初恋，不管她是谁。因为，我们的童贞只有一次， 我们永远不会忘记自己奉献出的第一次。

情态动词的否定

如果否定词not没有与情态动词的缩写形式一起被提置句首，而是直接置于 谓语动词之前，这是的被否定就是谓语动词，即“某事不应该做”

当否定词与情态动词的缩写形式放在一起时，被否定的就是情态动词，是 用来加强“请求”的情态含义，强调“某事应该做”

例句：

Will you please not get into the room? 你能不进这个房间里来吗？

Won't you please get into the room? 你难道就不能进这个房间里来吗？

Could I please not go to the party? 我能不来参加聚会吗？

Couldn't I please go to the party? 难道我不能来参加聚会吗？

规律

推测用法的情态动词，一般是内部否定，即否定的是谓语动作。

基本用法的情态动词，一般是外部否定，即否定的是情态意义。

例句

You can leave now,but he may not leave.

Tom will come,but John may not come.