情态动词（一）

1.           情态动词

can/couldmay/might must will/would shall should need

 

 

2.           can / could

 

2.1能，有能力做…… could 是can过去时

 

Icould kill you with my thumb.

 

 

2.2客观可能can表客观上可能  50% could表可能   40 %

 

Anybody can make mistakes.

任何人都会犯错误。

 

2.3        can/could用在否定句和疑问中表否定推测 90% could的语气更弱

 

It can’t be real. It must be fake.

 

2.4        表请求/许可（非正式） could更委婉 此时否定can’t表示禁止

---Can I have a look at your book?

---Yes, of course you can.

 

2.5        could have done 表示之前本来有可能发生，但实际没有

 

I could have passed the exam easily but I didn’t pay enough attention

 

2.6        couldn’t have done表示之前不可能做了某事

 

Hecouldn’t have gone to Shanghai.I saw him only a while ago.

 

3.           may / might

 

3.1 请求/许可（正式） might更委婉may not表不同意、拒绝

 

May  I trouble you to pass me the book?

 

在否定句中表：不同意，拒绝

 

--Can I leave the table now?

--I’m sure you can, but you may not.

 

--我可以离开饭桌了吗？

--你可以，但我不允许。

 

3.2 表示祝愿

 

May the road rise up to meet you 祝你一路顺风

 

3.3        may/might 表推测、可能性may 40%  might 30%

 

She may come or she might not.

 

Our customers may not be building cabinets or outdoor decks; we try to do that for them.

 

cabinets英: ['kæbɪnət]
n.
柜；【物】(机)箱；内阁；〈英〉内阁会议(室)
adj.
内阁的；小房间用的；小巧的；细木工做的
 

may/might as well不妨

 

You may as well eat something at midnight

 

3.4 may/might have done对过去发生的事进行不太肯定的推测表示过去有可能发生了……

 

He may / might have been hurt seriously in the car accident.

他可能在这起车祸中受了重伤。

 

4.           must

 

4.1 必须、一定要！（主观）mustn’t 表禁止

 

•        I must learn another language.

•        主观想法=I want to…

 

•        You must be back before 10 o’clock.

•        叮嘱或命令=I want you to

 

•        She must do it herself.

•        说话人的意志=I want her to

 

4.2 一定、准是！表非常肯定的推测

 

There must be a mistake

 

4.3       偏要

 

Why must you find another job while you have got one?

 

4.4        must have done对过去进行肯定推测 之前一定……

 

When I called her, there was no answer. She musthave been out.