It's too strange that they should have left without saying goodbye to us.这句是强调句吗 还是that为主语从句这里should是什么意思？

It's too strange that they should have left without saying goodbye to us.这句是强调句吗 还是that为主语从句这里should是什么意思？
It's too strange that they should have left without saying goodbye to us.
这句是强调句吗 还是that为主语从句
这里should是什么意思？

It's too strange that they should have left without saying goodbye to us.这句是强调句吗 还是that为主语从句这里should是什么意思？
that引导主语从句这我觉得没错,但是后面的should have＋过去完成,而且是否定形式,应该翻译成不该发生某事却发生了,是情态动词的用法.

这是一个that引导的主语从句，it是形式主语。that后面用虚拟语气should+动词原形，should可以省略。

太奇怪了,他们离开也没向我们说再见。