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?
问题描述：
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?
答
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