用need提问时,肯定回答为must,否定回答为needn’t或don’t have to。
如:—Need I stay here any longer?
—No. you needn’t /don’t have to.
need还可以作实义动词,此时有人称、数和时态的变化,如果是人作主语后边多接动词不定式。
如:I need to do it right now.
如果是物作主语,一般用need doing与need to be done,这种情况下应注意两点:
② 该动名词可以改为其动词不定式的被动形式而句子的意义不变。
例如:. The door needs painting. = The door needs to be painted.