在非限制性定语从句中 当主句是否定句时,只能用as
2个回答

在非限制性定语从句中,which和as引导定语从句时的区别

a.which引导的从句不能放在主句前,而as引导的从句则既可以放在主句前,也可以放在主句后.例如:

As (正确) is often the case,he is absent.

Which (错误)

He saw the girl,as (正确) He had hoped.

Which (正确)

b.用能做关系代词,as和which都可以指代一个句子,但as有“正如”、“就像”之意,which则没有此含义.

He is a foreigner,as I know from his accent.(as指代一个句子,意为“正如”、“就像”)

He has to work on Sunday,which he doesn’t like.(which指代一个句子,没有“正如”、“就像”)

c.当从句的谓语动词是be或相当于联系动词的seem,become等时,可用as或which作主语.但当从句的谓语是行为动词时,只能用which作主语.

例如:

He married her,as (正确) was / seemed natural.

Which (正确)

He saw the girl,as (错误) delighted him.

Which (正确)