need dare used to had better would better
情态动词 的否定 直接 加not
实意动词就会有时态和人称的变化
You needn't come so early
You don't need to come so eary. // 实意动词
He doesn't need to come so early.
Need i do it now? Yes, you must/have to
Yes, you ought to/should
No, you needn't
No, you needn't have to.
need something 只能是实意动词
I need your help
we need express little surprise.
need作为情态动词， 极少用于肯定句
只有用于 表示否定意义的语境中
需要去做 需要被
I dare to swim across the river.
I don't dare to swim across the river
Don't you dare to touch it.
i dare not go out at night.
If you dare speak to me in that way, shall be punished.
I need to buy a bike
My bike needs to be repaired.
My bike needs repairing.
you had better not do it again.
You'd better be doing now
Better stay in side today.
Hadn't we better go now.
Had we better not go now.