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needn't后面必须是do sth.可是我看电视时发现有一句和老师讲的不一样,Need not to know(无需知道).那need究竟有怎样的用法呢?可以帮我分析一下needn't do sth和needn't to do sth这两者的区别吗?
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.