这句话里为什么要用Be?you must be home at night.如果把be换成come或back不也行吗?这有什么区别?如果是 come home这个home应该是名词吧~那跟在be后面home是什么词性?

It must be terrible to be grown up!这句话里为什么要加be呢? You must be on time.为什么要用be? do not talk too much若用must改写这句话,为什么是You must not talk too much..也就是说 ,为什么要去掉do?一句话中可以出现2个动词把,比如若是Be quiet.用must改写的话,是：You must be quiet.中间的be没有去掉啊 You need’t be so rude about it.这句话里为什么要加be呢? 这句话里为什么要用Be?you must be home at night.如果把be换成come或back不也行吗?这有什么区别?如果是 come home这个home应该是名词吧~那跟在be后面home是什么词性? when i must be home这句话对吗.课文里是when must i be home. i must be leaving now这句话是什么时态 为什么be后用leaving be grown up被动词态中为什么用be?it must be terrible to be grown up.这句话中be grown up中的be为什么不用is?这里没有什么条件要用be原形啊. you must (be joking)为什么要用(be joking),用joke行吗? you must be there on time.此句中为什么要用be ,get不行吗? you will be must not drink here,这句话对吗i heard she got married,此处为什么要用married，为什么不是i heard she had got marry,why is the above sentence not right? you must be improve your spoken English这句话是正确的吗?要不要去掉be? I'm afraid I must be going .这句话为什么用被动语态? You must not be late again tomorrow.为什么要加be动词?You must not be late again tomorrow.为什么不能：You must not late again tomorrow. You must be dreaming 为什么不说 You are must dreaming? You must be home at half past ten.为什么要用be,be是在什么情况下用的? i think you must be a teacher是什么意思must be为什么不是must are?must We must be must be这句话意思