as we all know的高级表达

as we all know的意思是正如我们所知或者众所周知，这是以句子充当先行词，as作关系代词的定义从句。它的高级表达是as is known to us all。

例如

众所周知，中国是一个历史悠久的国家。

As is known to us all ， China is a great country with a long history.