as is known to..为什么这么用啊?

来源:百度知道 编辑:UC知道 时间:2024/06/29 01:54:52
as is known to..为什么这么用啊?怎么用啊?怎么没有了it啊,请详细解释一下谢了!

是非限制性定语从句,在句首用as如 As is known to us,the Great Wall is very famous.如在句中就用which
如The Great Wall is very famous ,which is known to us.
至于it如放在句首该用It is known to us that the Great Wall is very famous.

正如。。。所知道的那样
如:As is known to all,the earth is not flat。众所周知,地球不是圆的。

As is known to.. 是as引导的非限制性定语从句,后面加句子以","隔开.
It is known to.. 中it是形式主语,后加"that+句子"