情态动词can,may,must,need等的一般疑问句,它们的肯定和否定回答各是...答:the office.用may回答.can表许可的时候.can i smoke here?--no,you can't .yes ,you can.may i ……?我可以……吗?表许可.yes,you may./no,you may not.must i.和need i .回答一样.肯定回答是yes,you must.否定回答是no,you needn't/no ,you don;t have to.有疑问欢迎追问!