如果 非要说的话,你记住
as引导非限制性定语从句既可放在主句之前,也可放在主句之后,用来修饰整个句子.通常用下列句型：as is known to all,as is said,as is reported,as is announced,as we all know,as I expect 等.
e.g.As I expected,he got the first place again in this mid-term examination.正如我所预料的那样,他在这次期中考试中又获得了第一名.
所以 以后看见as is known to all,as is said,as is reported,as is announced,as we all know,as I expect 这些的时候 用as 记住好了,特别喜欢考