英语中情态动词的用法归纳总结

Answer 1

归纳总结:情态动词用法ABC

情态动词表示说话人对某一动作或状态的态度,或表示主观设想。情态动词有自己的词义,但不能单独作谓语动词,必须和后面的动词连用构成谓语,没有人称和数的变化。常用的有can, may, must, need等。情态动词是中考测试的重点,准确把握情态动词在具体语境中所表达的意义至关重要。

一、can的用法
1.表示能力,有"能"、"会"、"能够"的意思。例如:
Can you drive a car?
2.表示可能,常用于否定句或疑问句。例如:
Can it be true?
Today is Sunday. He can't be at school today.
3.表示允许,口语中代替may,有"可以"的意思。例如:
You can use my car.
4.can和be able to 的区别:
can表示能力时,可以用be able to代替;can只有can和could两种时态,而be able to可用于其他时态;be able to强调"通过努力有能力做到",如果表示"某事已经成功"应用 be able to,而不用could。例如:
He was able to leave Europe before the war began.
二、may的用法
1.表示许可(否定回答用can't或mustn't)。例如:
-May I take the magazine out of the reading room?
-No, you can't (mustn't).
2.表示可能,通常只用于陈述句中。例如:
It may rain this afternoon.
3.表示祝愿,用于祈使句中。例如:
May you have good luck!
三、must的用法
1.表示必须、应该(否定形式用needn't或don't have to )。例如:
-Must I finish the work before dark?
-No, you needn't / don't have to. You may leave it for tomorrow.
2.must not (mustn't)表示强烈禁止。例如:
You mustn't get to school late.
3.表示推测,只用在肯定句中,"一定"、"想必"之意。其否定意义"不可能",用can't be形式。例如:
-The light in her room is still on; she must be at home now.
-She can't be at home. I saw her out just ten minutes ago. She forgot to turn off her light.
4.must和have to的区别:
must表示说话人的主观看法;而have to强调客观情况迫使人不得不……;must只能表示现在"必须",表示过去的事情要用had to;have to有时态、人称和数的变化。must和have to的否定意思不同。比较:
You mustn't do that.(你千万不能做那件事。)
You don't have to do that.(你不必做那件事情。)
四、 need的用法
need作情态动词时表示"需要",主要用于否定句和疑问句。例如:
-Need we finish the work today?
-Yes, you must. / No, you needn't.

Answer 2

情态动词后面加动词原形，例如
must do sth.
mustn't do sth.
may do sth.
may not do sth.
should do sth.
shouldn't do sth
......

Answer 3

1) may(might) have + done sth, can (could) have + done sth 表示过去，推测过去时间里可能发生的事情。
Philip may (might) have been hurt seriously in the car accident.
Philip can (could) have been hurt seriously in the car accident.

2) must have +done sth，对过去时间里可能发生的事情的推测，语气较强，具有"肯定"，"谅必"的意思。
---Linda has gone to work, but her bicycle is still here.
---She must have gone by bus.

3) ought to have done sth, should have done sth
本应该做某事，而事实上并没有做。否定句表示"不该做某事而做了"。
You ought to (should) have been more careful in this experiment.
He ought not to have thrown the old clothes away.（事实上已扔了。）
ought to 在语气上比should 要强。

4) needn't have done sth 本没必要做某事
I dressed very warmly for the trip, but I needn't have done so. The weather was hot.

5) would like to have done sth 本打算做某事
I would like to have read the article, but I was very busy then.

参考资料：http://www.52en.com/whbm/grammar/index.htm