情态动词问题

1 may I~~~~~表示请求许可，否定回答用must not表示“不可以，禁止”的意思。例如：
---May I come in?
---yes,you may/no,you must not
2 yes,you must/no,you need not.
3 回答Must~~~~~？引出的问题，肯定回答用must ,否定回答用need not 或don not have to.而must not 表示“禁止”之意。例如：
---Must I finish my home work now?
---yes,you must.(no,you need not/do not have to)
4 yes,you should/no,you need not.
5 yes,you can/no,you can not.

May I...
Yes,you may /No,you may not
Need I...
Yes,you need /No,you neeed not
Must I...
Yes,you must /No,you must not
Should I...
Yes,you should /No,you should not
Shall I
Yes,you shall /No,you shall not