may,can,must,need引导的一般疑问句的肯定回答及否定回答

may I do...Yes,you may.No,you can't/ mustn't.Can I do sth?Yes,you can.No,you can't.Must I do sth?Yes ,you must.No,you needn't./ No,you don't have to .Need I do sth?Yes ,you must.No,you needn't.