选as,关系代词as代替整个主句,并在从句中作主语.as引出的从句为非限定性定语从句.
再如：
She has married again, as was expected.
她已再婚,这是意料中的事.
We are tired, as anyone can see.
我们累了,这是有目共睹的.
which和as都可在非限定性定语从句中代替整个主句,这就要从意思上考虑.as还有如……那样的意思.The exam was continued at the beginning of the new term是一件事实,这个事实是可以announced的吗?只能说如……所宣布的那样,……继续进行了.