don't have to=need't =don't need to?
问题描述：
don't have to=need't =don't need to?
答
是的.均可表示不需要,没有必要.存在can be/must be ，can’t be 而没有mustn't be 对吗？有mustn't be ，不过意思是不可能。有个题目 isn't your teacher over there？ no，it（）be him 其中两个选项can'tmustn'tcan't be不可能是我的老师。musn't be 是不能