题目

看两个例子,帮我总结一下must be的用法!
1.He must be home before six o'clock.
He has to be home before six o'clock.
2.He must be tired.
I think he is probably tired.
这是课后练习中的题目要求,要求模仿例句改写以下句子：
He must be here at six o'clock.
He has to be here at six o'clock.
He must be busy.
I think he is probably busy.
句中的must be应该是“一定”的意思吧,为什么有的改写成have to ,有的改写成probably?

提问时间：2020-10-07

答案

must后面接实意动词表达非常肯定、或命令：He must do it.他必须（命令）肯定会（把握很大）做.
后面接表示状态的词(be happy/be 18/be at home)接进行时（must be doing)以及完成时（must have done)则表达说话人对这件事的推测.
have to 是被逼无奈.
翻译后比较：他六点前肯定在家、不得不在家