dare的两种用法

dare的两种用法

Dare的意思是“有勇气做某事”，它也有两种用法：

dare 作实义动词

* as an ordinary verb followed by an infinitive with to, with s in the third person singular and with questions and negatives formed with do:

作为实义动词时，接带to的不定式，第三人称单数作主语时加s，疑问句和否定句用do来构成：

He never dares to criticise her for wasting money and she doesn't dare to interrupt him when he's working.

他从不敢批评她浪费钱，而她不敢打扰他工作。

dare 作情态动词

作为情态助动词时，接不带to的不定式，第三人称单数作主语时不加s，疑问句和否定句不需要用do来构成：

Dare she tell him what she thinks about him? She daren't say anything. He will only shout at her. "How dare you speak to me like that?" he will say.

她敢告诉他她对他的想法吗？她什么也不敢说。他只会对着她咆哮：“你怎敢那样对我说话？”他肯定会这么说。

比较

Differences in use are not as fixed or clear cut between doesn't dare to and daren't as they are between doesn't need to and needn't, except in expressions or collocations such as:

doesn't dare to与daren't在用法上的差别不像doesn't need to和needn't那么固定或清晰，除了在以下这些表达和搭配中：

* How dare you?你怎么敢？

eg: How dare you walk away when I'm talking to you?我在跟你说话的时候你怎么敢走开？

* I dare you to…我谅你不敢……

I dare you to go up to him and ask him for a date.我谅你也不敢走到他面前请他跟你约会。

* I dare say…我敢说……

I dare say you're pretty hungry after all that cycling.我敢说你骑了那么久后肯定饿死了。

In this last example, I dare say means I suppose.最后一例中的I dare say的意思是I suppose，我料想。

情态动词如何表猜测

情态动词用于肯定猜测

1. must用于肯定句，表示较有把握的推测，意为“准是，一定”。后面接动词原形，表示对现在的推测。如：

-I've had no sleep for 48 hours. 我已经48小时没睡觉了。

-You must be very tired. 你一定很累了。

2. should用于肯定句中，语气次之，意为“很可能，应该”，指按常理推测。如：

They left yesterday. They should be home by now. 他们昨天就离开了，现在该到家了。

3. can用在肯定句中，表示理论上的可能性。如：

Smoking can cause cancer. 吸烟有可能引起癌症。

4. may用在肯定句中，表示对现在把握不大的推测，意为“也许，可能”。如：

Don't play with the knife. You may cut yourself. 不要玩小刀，你可能会伤了自己。

5. could, might也可表示推测意义，常用在过去时态中；但在某些场合下，为了使语气更缓和、更委婉，常用could, might代替can, may。如：They saw something in the sky last night. It could/might be a UFO. 昨天晚上他们看见天空中有个东西。它有可能是不明飞行物。

You may/might/could be very tired. 你可能很累吧！

情态动词用于否定猜测

1. 表示否定的推测时，can't/couldn't语气最强，指“不可能”，带有惊异、怀疑的感情色彩。如：

The story sounds reasonable, but it can't be true. 这个故事听起来合情合理，但不可能是真的。

2. 语气不很肯定时，常用may not或might not表否定推测，意为“可能不，也许不”。如：

He may not/might not be at home. 他可能不在家。

情态动词用于疑问句表猜测

疑问句中的推测，常用can或could，意为“可能”。如：

Who can it be? Can it be Jenny? 那会是谁呢？是珍妮吗？

The money has disappeared! Who could have taken it? 钱不见了！会是谁拿去的呢？

Oh, how could you be so stupid? 哦，你怎么会这么愚蠢呢

can have done用法小结

can have done 通常只用于否定句和疑问句。用于否定句时表否定推断，推测肯定没做；用于疑问句时意为“难道真的做了吗”，表示怀疑。例如：Can he have done such a foolis h thing? (= Is it possible …?)他会做这样的傻事吗？（表怀疑）

He can't have taken it home.他不可能把它带回家了。（表不可能）

could have done