AS在从句中的用法小结
一.As在各种状语从句中的用法:
1. AS用于时间状语从句中,表示从句动作与主句动作同时发生, “边….边….”,而且主要指一段时间,但有时候和when一样也可指一点时间。
They shouted slogans as they pasd the square
2.As用于原因状语从句中,表示的原因语气较弱,其原因多是对方所知道的,他引出的原因状语从句常常置于句首。
As he wasn’t ready in time, we went to the bar without him.
3.AS用于让步状语从句中，常常被转换成一个部分倒装结构，含有强调的意味。
1）Small as (=though) the stars appear, they are really large bodies.
2）Tired as she was, she continued to prepare for her lecture tomorrow.
4.AS引导方式状语从句时，意思是“如同”、“就像”（in the same manner that…..）,可以修饰动作和状态。
例如：Air is to man as water is to fish.
二．AS在定语从句的用法
1.AS引导限制性定语从句时，主要用在“such….as”,”the same…as”的结构中，可倒替先行词是人和物的名词.在“the same…as”的结构中as 也可以用that来代替
1）Let’s discuss only such questions as concern us!(as作主语)
2）I have never en such kind of people as they are.(as作表语)
3）This is the same scarf as/that I have bought in HK.(as作宾语)
2.AS引导非限制性定语从句时，代替整个主语，对其进行说明。该从句的位置比较灵活，可位于主句前面或者插在主语中间，或者位于主句后面。常常由逗号将其主句隔开。“正如….” “正像….”
1）She is a southener,as(=which) I know her accent.(as代替前述句在从句中作宾语)
2）As was usual with the old man,he went out for a walk with his dog after dinner.
(as代替后述句在从句中作主语)
