在英語的動詞當中，凡是用來刻畫人的情感動作的動詞，我們稱之為情態(tài)動詞，情態(tài)動詞有著具體的漢語意思。但卻不能獨立作謂語和后面的行為動詞一起構成和成謂語。

概念

在英語的動詞當中，凡是用來刻畫人的情感動作的動詞，我們稱之為情態(tài)動詞，情態(tài)動詞有著具體的漢語意思。但卻不能獨立作謂語和后面的行為動詞一起構成和成謂語。區(qū)別于其他的行為動詞，情態(tài)動詞沒有人稱和數(shù)的變化，有少數(shù)的時態(tài)現(xiàn)象—— 一般時、過去時、將來時等。

應用

一.Can

1、can表示說話人的能力，常譯作能、能夠、會。

eg：I can speak English very well.

Can you swim across the river? Yes, I can/ No, I can’t.

2、 can可以用來表示說話人的客觀可能性，通常應用于否定疑問句式中。

eg：People can’t live without water.

Can you finish the jobs in three hours?

Can this be true.

3、 在口語里，can表示允諾、允許、可以。等于may，但是may的語氣重于can。

eg：Can I come in? = May I come in?

Can I use your bike? = May I use your bike ?

*表示允許可以may mightcould can

4、 在“過去時”的語境里，通常用could 表示它的過去式，用be able to 短語（was/were）

而could通常用來在一般現(xiàn)在時的語境里表示委婉語氣

eg：Could（can）you show me the way to the supermarket?

5、 can表示猜測

（1）對現(xiàn)在狀態(tài)的一種猜測，只能用在否定疑問句中。

eg：Zhang can’t be ill really?

This can’t be done by him.

（2）對現(xiàn)在動作的猜測

eg: The boy can’t be telling lies.

Mary works so hard, now, she can’t be sleeping.

（3）對過去動作的一種猜測

eg：He can’t have gone to the bookshop yesterday.

Mother couldn’t have said it.

6、 can（could）慣用法

（1）can’t wait to do 迫不及待做…….

eg: Children can’t wait to eat apples in the basket.

（2）can’t help doing 情不自禁做某事。

eg：When I heard the news I can’t help laughing.

（3）can’t but do 不得不

eg：I can’t but refuse you.

We can’t but ask him about it.

*can’t but do 區(qū)別于 have to

have to 表示說話人在客觀條件下的無奈所為，表示說話人的一種無奈情緒。

can’t but do強烈突出說話人內心的反抗反對情緒。

二.May

1、 may表示可能性，也許、可能，通常應用于正式文體

eg：China may make friends with many people all the world.

Boss said that you might drive this new car.

You may not take this book out of the reading room.

2、 may表示允許、允諾，口語中等于can, may比can語氣強。

eg：May I speak here?

May I go in to the room to see her? Yes, you may. No, you mustn’t.

*may 表示允諾、允許，其問句回答的排序

eg：May I use your pen?

Yes, you sure please. ok…..

No, you mustn’tyou had better notplease don’tyou can’tI don’t

think you canyou may not

3、 might在表示上述概念時，語氣更委婉

eg：She was afraid that they might not her idea.

He asked if he might look through your album.

4、 may 表示推測，通常用于肯定句中

（1）對現(xiàn)在狀態(tài)的一種推測。

eg：He may be very busy now.

（2） 對現(xiàn)在動作的一種推測。

eg：Where is Tom? He may(might) be having breakfast at this moment.

（3） 對過去動作的一種推測。

eg：Where were you last night?

I might have watched TV or have read the novel at home.

5、 may的固定用法

（1） may在祈使句中至于句首表示祝愿。

eg：May you succeed!

May god be with you.

May you live to be one hundred.

（2） may在狀語從句當中構成特殊的狀語結構。

eg：They wanted to go to the Chinese restaurant they might eat the soup.

（3）may/might as well + 動詞原形表示 還是….

eg：You may as well post him the letter again.

It was snowing I might as well stay at home.

三.must / have to

1、must表示 必須、一定、一定要，是所有情態(tài)動詞當中語氣最強的，突出表現(xiàn)說話人的一種指責，即說話人主觀上應該………

eg：Everybody must obey the rules.

People must do everything step by step.

Must we hand in our working plan this week?

Yes, you must. No, you needn’t /you don’t have to.

have to 必須、不得不、表示說話人客觀條件下必須要做的事情，烘托說話人的無奈情緒。

eg：I had to answer the same question three times in class.

I hope you will have to finish your schooling this year.

2、must表示推測，但通常應用于肯定句式。

（1）對現(xiàn)在動作的一種推測 must be doing

eg：You haven’t warm clothes, you must be feeling cold.

（2）對現(xiàn)在狀態(tài)的一種推測。

eg：ZhangHua must be in his room, because he telephoned me five minutes ago.

（3）對過去動作的一種推測 must have done

eg：The road is white, it must have rained last night.

You must have caught the first train, if you have got up early.

四.need

1、need是特殊的行為動詞，具有雙重性，即情態(tài)動詞和行為動詞兩種形式，通常肯定句式用行為動詞形式need to do，否定和疑問用情態(tài)動詞形式。

eg：You need to go there by yourself.

He needs to read it for many times.

We needn’t worry about him.

Heed I finish my job today?

Need I come here tomorrow? Yes, you need / Yes, you need / Yes you should

Yes, you may.Yes, you must.

正確排序：Yes, you must / Yes, you have to / Yes, you ought to / Yes, you should / Yes,

you need.

2、need的特殊用法，可以表示責備。

need have done 需要做而沒有做的事。

needn’t have done 沒有必要做反而做了的事。

eg：You need have done it three days before.

The train is close to us, you needn’t have hurried their early.

3、need的固定用法

need doing = need to be done 表示被動意義

eg：This young tree needs watering.

五.dare

1、dare與need一樣，具有行為動詞，情態(tài)動詞雙重性，肯定句為行為動詞，否定疑問句為情態(tài)動詞。

eg：Mary dares to go there alone.

Dare you go through the forest at night? Yes, I dare.

She dare not stay at home alone.

No one dared speak of it again.

2、dare的慣用法

I dare say 我敢說。

eg：If your father dies, who will get the money? I dare say my uncle will.

六.ought to / should

1、ought to指說話人在道義和義務上應盡的責任和義務，使用ought to具有一定針對性，通常是按理推斷。

should表示應該，只是強調單從人說話的角度上看指 勸告、建議，語氣比ought to 弱。

eg：You are her mother; you ought to look after her well.

The youth ought to defend our mother land.

You ought to take your parents’ suggestion (advice).

Ought I to obey the rule in your class?

Yes, you ought to / No, you oughtn’t

Oughtn’t we to do everything possible to stop pollution?

We should study foreign language very hard.

One should be selfish.

We should encourage the newer, for we are his classmates.

2、should在虛擬語氣當中可以構成特殊的謂語結構

eg：I suggested that he (should) be sent to the hospital at once.

should 在虛擬語氣中放在疑問，否定句中表示驚訝

eg：I shouldn’t worry if I were you.

Why should she do that?

3、 ought to, should 表示責備

Ought to (should) + be doing

Oughtn’t to (should) + be doing 指說話人對現(xiàn)在動作的一種責備。

Ought to (should) + have done 表示說話人對過去動作的一種責備。

eg：You should be washing your clothes, why are you playing here?

Children shouldn’t be watching this film, they should be at school.

You should have gone over your lessons.

You oughtn’t to have watch TY so late.

I’m feeling sick. I oughtn’t to have eaten so much ice-cream.

七.will / shall

1、will 從情態(tài)動詞的角度上看，充分地體現(xiàn)了will 的原始漢意 意愿、愿意 表示這一層意思will可用于多種人稱。

eg：I will do everything for you.

Who will go with me?

2、will在疑問句當中通常在和第二人稱搭配，表示征詢對方意見，表示….好嗎？

eg：Will you help me carry this box?

Will you open the door for me, please?

Won’t you come over?

3、表示某種習慣或某些傾向的動作，通常是it主語

eg：Fish will die without water.

What’s the matter with the door? It won’t lock.

Which do you want, this or that? Either will do.

4、 shall 在應用時比較強調人稱的搭配，即不同的人稱代表不同的語境，shall應用于第一人稱時

表示說話人征詢對方意見。

eg：What shall we do next?

shall應用于第一，第三人稱時，除了表示征詢對方意見以外，還表示向對方委婉的請求。

eg：Shall I open the door?

Shall we sit here?

Shall the boy wait outside? = Do you want the boy to wait outside?

shall應用在第二，第三人稱時，表示說話人給予對方警告和命令，允許或威脅。

eg：You shall fail if you don’t work harder. (警告)

He shall have the book till he finished reading it.

You shall do as t say.允許

八.used to / would

1、would 表示意愿，愿意即 will 的過去式，語氣更加委婉些，通常是will發(fā)生在從句里。

eg：He said that he would try his best to help us.

Don’t worry, I promised that I would do.

would 在表達will 的意愿，愿意的語氣時，通常會形成特殊的句型，句式。

eg：Would you please have lunch with us?

Would you pass me the book on the desk?

Would you like me to carry it for you?

That would be kind of you.

2、would表示過去常常，即主語常有的一種習慣，但只局限于過去某一階段的動作。

eg：I would drink green tea.

When he was young, he would smoke a lot.

I have still remember the boy, He used to ask some stupid questions.

3、 would 可以用在特殊的語境里，表示說話人的情感或情緒上的宣泄，常用于否定句，肯定句，不用再疑問句里。

eg：I don’t really understand you, why?

----No, you wouldn’t. (不指望你明白)

4、 would的慣用法

would可以用在虛擬語氣中

eg：I wish the rain would stop for a moment.

Would rather do than do？

would mind doing 做……你介意嗎？

eg：Would you mind opening the window?

5、 used to過去常常

（1） 和would比較起來，used to 強調過去常常發(fā)生的某事而現(xiàn)在不是。used to沒有其他的詞形變化，不能與其他的情態(tài)動詞連用，表示從前經(jīng)常發(fā)生的動作現(xiàn)在卻不復存在了。

eg：My uncle used to take cold bath in winter.

Jams used to have fat meat.

（2） used to 有時根據(jù)上下文可判定used to后面的成分，所以情態(tài)動詞used to后面的行為動詞可省略。

eg：I can’t stand as much as I used to.

（3）used to 的否定形式

在used to前面用didn’t表示

I didn’t use to smoke.

在used to前面加never

When I was as young as you, students never used to say anything against their teachers.

在used to 后面加not

The woman in our office used not to clean the room.

（4） used to 在反意疑問句中的表示

eg：John used to be a policeman, didn’t he? / used not he?

--------Yes, he did.No, he didn’t.

--------Yes, he used to.No, he usedn’t to

九.had better

最好---；應該-----（=should 約等于 ought to）

1、與第一人稱I ，we 連用時，表示說話人的某種意向。

eg：I think we had better wear warm clothes in this season.

We had better wait for her for a moment.

2、與第二人稱連用時，表示說話人的忠告，勸告。

eg：You had better go immediately lest you miss the good chance.

You had better read the test again and again.