as引导的定语从句

(1) as引导的定语从句修饰表人或物的先行词，即先行词可以是人也可以是物；在定语从句中可以做主语、宾语或表语；常用于the same…as…/such…as…/as(so)…as…句型，as不论在定语从句中作何成分，均不能省略。

①Such teachers as know Tom think him bright. 先行词为人such teachers， as作主语

②I’ll buy the same bike as I lost yesterday. 先行词为物the same bike，as作宾语 ,指同一类事物

※此时注意和the same … that … 引导的定语从句的区别

It’s the same bike that I lost yesterday. that引导定语从句，作宾语，指同一个事物

※ She wore the same dress that she wore at Mary's wedding. (the same…that…特指同一个)

她穿着她在Mary婚礼上穿过的同一条裙子。

She wore the same dress as her young sister wore. (the same…as …泛指同一类)

她穿着和她妹妹所穿的一样的裙子。

That is the same watch as I lost. 那块手表和我丢失的一模一样。(the same…as …泛指同一类)

That is the same watch that I lost. 那就是我丢失的那块手表。 (the same…that…特指同一个)

③The school is just the same one as it was 10 years ago.

先行词为物the same one (school), as作表语

It’s so heavy a box as no one can lift. 先行词为物so heavy a box，as作宾语

此时应注意as引导的定语从句和结果状语从句such / so…that… 的区分

It’s so heavy a box that no one can lift it. 结果状语从句so… that… 如此… 以至于…

※He is such a good student as is liked by everyone. (定语从句，as在从句中作主语)

He is such a good student that he is liked by everyone. （结果状语从句such…that…） that在从句中不充当任何成分，故不是定语从句，而是结果状语从句

(2) as引导的非限制性定语从句可以修饰整个主句, 可以放在主句前，主句后或插入主句中间。此时as含有“正如…” 之意。常用的as引导的非限制性定语从句固定表达有：

as we all know / as everyone knows / as is known to all / as is well-known (众所周知)/ as I can remember(正如我所记得的) / as we expect / as was expected (正如预料的那样)/ as often happens / as we all can see / as can be seen / as has been said before (如前所述)…

As everyone knows, Shakespeare is a famous writer.

Shakespeare is a famous writer, as everyone knows.

Shakespeare, as everyone knows , is a famous writer.

(3)注意which引导的非限制性定语从句也可以修饰整个主句, 但不能放在主句前，常译为“这一点、这件事…”。

She is working hard, which everyone can see. which引导的非限制性定语从句不能放在主句前

She is working hard, as everyone can see.﹦As everyone can see, She is working hard.

(4)注意当修饰整个主句时，as引导的非限制性定语从句含“正如”之意，因此在意义上不能和主句相抵触；which引导的非限制性定语从句则无此限制。如：

Our team lost the game, which was unexpected. 我们的球队输了比赛，这一点是未预料到的。此时不能用as。

Our team won the game, as was expected. 我们的球队赢了比赛，正如预料的那样。

as在定语从句中的详细用法