need,may,must引导的问句(作情态动词),肯定和否定分别是什么?

问题描述:

need,may,must引导的问句(作情态动词),肯定和否定分别是什么?

must-Yes,you should./No,you needn't. need-Yes,you should/may/can/need./No.you needn't/musn't. may-Yes,you may/can./No,you musn't/can't.