can,t mustn,t用法区别词

Question

如题所述

Answer 1

1.mustn't在英语中不能用于表示推测,但是可以表示“禁止/不允许”之意.
如：You mustn't smoke here.在这里你不许抽烟.
2.can't/couldn't表示推测时,意思是“不可能...”,语气非常坚决的否定推测.
根据动作发生的时间,一般分为以下三种情况：
1）进行式（对正在发生的事情的否定推测）：can't be doing sth
如：It's already ten o'clock.My father can't be sleeping now.
2）完成式（对过去的动作的否定推测）：can't/couldn't have done sth
如：He is at schoool,so he can't/couldn't have stayed up last night.
3）一般式（对现在/将来情况的否定推测）：can't do sth
如：Your answer can't be true.

Answer 2

can't是不能，mustn't是不准，有关于法律的，mustn'比can't程度要深，结合句义就可以知道了