Question

need的用法 老师讲过,需要做...用need to do sth,而need可以看作是情态动词也可以看作是动词,所以

Answer 1

1. 你老师讲得没错.

情态动词: need (not) do sth

行为动词: need sth/sb

need to do sth

need sb to do sth

sth need doing=sth need to be done

名词: there be no need for/of sth

there be no need (for sb) to do sth

in need (of...)

2. 否定形式应该是 needn't do sth

而need not to do sth也是有的(但不能缩写成needn't to do sth)

因为to do sth这个不定式本身也有否定式,不定式的否定全部是在to前加上not/never等否定词

3. 但是两者在翻译差别很大啊,要记住.

needn't do sth 没有必要做某事

need not to do sth 不做某事有必要

如: You needn't ask him.

You need not to smoke as a student.