The truth is that we are in a situation previously unknown to man .

问题描述:

The truth is that we are in a situation previously unknown to man .
that/this意为____,修饰____,相当于__
该句主语,谓语

事实上我们是在一个前所未知的状况里
主语谓语我不懂怎麼分
但意思是这样