Dare, meaning have the courage to do something, can also be used in two ways:

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

as a modal auxiliary verb followed by an infinitive without to, with no third person singular s and with questions and negatives without do:

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。