what we all know,在这里属于what引导的名词性从句；敬正
As we all know属于亮肢悔as引导的非饥裂限制性定语从句；
例如： What is we all know is that YaoMing used to be the best basketball player in China.
As we all know, Yaoming used to be the best basketball player in China.
你好 !
what we all know 是桐闷困名词从句,可以做主句主语, 表语罩知或宾语.
as we all know是状语从局念句.
what we all know是“我慎睁备们都知道的”意思，早滚as we all know是“宽毁正如我们所知道的”意思