must need shall may 的肯定回答和否定回答

must:
肯定must（必须）,否定must not/mustn't/needn't（不准,禁止）He mustn't be there 他一定不在那儿.Mustn't I smoke here?禁止在这儿吸烟吗?you mustn't smoke here.你不能在这儿吸烟.
注意,must 的否定也有用needn't的.Must I finish the work this morning?Yes,you must/No,you needn't.我必须早上就完成工作吗?是的,必须/不,不需要.
need:
肯定need(需要/必须),否定needn't.You need not go yet ,need you?Yes,I must/ I need to/ I have to/No,I needn't或者 No,I don't have to.你不一定要去,是吗?是的,我一定要/必须/不得不去/不,不一定要去.
shall(只和第一人称连用 we/I):
肯定shall（将/必将/可以/.好吗）,否定 shall not.注意,当回答中主语不再是第一人称,Shall要变成should.Shall I go to school?Good idea/Yes,you should./No,you shouldn't.但是回答主语仍旧是第一人称时,shall 不用变.Shall we go to school?Yes,we shall/No,we shall not/I'd love to,but I can't.
may:
肯定may(可以/许可/能),否定may not.注意过去式,虚拟语气或客气是用might/mightn't.May I close the window?Yes,go ahead/Yes,you can（一般不这么说）/No,I'm afraid you may not.
不可死记硬背,要根据具体情况选择合意的情态动词,也就是搞清楚这句话的“情态”是什么.有些情态动词的提问不一定要用肯定或否定回答.比如我可以关窗吗?你可以说,我有点热,先开着好吗?英语也可以这样回答.