正如之前所述

这个翻译成 As stated before ,可以吗？？
我想问 这里为什么 用 stated ?而不用ING形式呢？

As stated before ,
Mike说的对．
As stating before,[没找到这种用法］
As is stated,．．．
As I have stated before,．．．
以上两种有
As stated before the precise interpretation of linear understanding entails that phenomenal development takes place in the context of ...

Chris, as stated before, the beach is fine... My wife and i left Sunday at 7 am landed before 9 am mexico time. The shuttle was there waiting ...

...I don't think John's hearing is what it once was and he may have had a few too many drinks. ... As I've stated before...
Album (as is stated...before known) by Ernest.

去查了下语法书：as关系代词，引导的非限制性定语从句，可以放在句首，而which则不可以放句首．这时的as有＂正好．．．＂，就像．．．＂，＂由．．．而知＂的含义．当主句和从句内容上一致时，或者说从句内容顺着主句的意思说下来时，用as．若不一致，用which．＜＜英语语法新思维＞＞＂世界知识出版社＂------新东方学校实用英语丛书
[52页]
She has married again,as [which]was expected.
As(was)expected,she has married again.
所以as后用ing的形式，就不是定语从句了，而as成了介词［作为．．．］或是独立主格的连词［当．．．时候］，这些与定语从句的句子的意思不相符．

关于昨天的回答，请楼主见谅．

再摘两个句子,一个是主句和从句内容上一致[两句顺从］,另一个不一致［两句有转折］:
she is very careful,as her work shows.

The elephant is like a snake,which is not right.