as的用法总结

㈠、so that、so…that、such that、such…that引导状语从句的区别。so that 作为一个整体，充当一个连词引导状语从句，其前的主句完整。such that好像大多情况下跟在系动词后面，such可以理解为作系动词的表语，而that引出状语从句。

例：The difference is such that all will perceive it.

I did very well in English so that I was praised by Miss Green.

so…that 、such…that中so是副词，修饰后面的副词性、动词、形容词性的成分。such是形容词，修饰名词性成分。连词that引出状语从句。例：He is so honest that he will not tell a lie.

㈡、as 引导的定语从句，用在如下句型中：(先行词可是人或物)

①“as/so…as”，此结构中，第一个as或so它们都是副词，修饰主句的形容词或副词的原形，后一个as是关系代词，引导限制性定语从句。

例：In the city, I saw so grand a National Day celebration as I never dreamt of.(本句中so修饰形容词grand，as作为关系代词引导定语从句且在从句中作of的宾语。)

②such…as(这个句型中，such是代词，作名词的定语，修饰其后的名词，as是关系代词，参见《大学英语语法》P120)，“such as”连用这种结构与分开的结构式一样的，只是把such与as放在一起而已。Such people as were recommended by him were reliable.（such作people 的定语，as引导定语从句，在从句中作主语，先行词为people。）

I’ve never seen such a talented young man as he is.(such作a man的定

语，as引导定语从句，在从句中作表语。先行词为a man)

He is not a man such as I admire.“他非我钦佩之人。”

He is not such a man as I admire.

③the same…as(本句型中，same为代词，其前必须有the。即“the same”是不分开的。其可在从句中作主、宾、表、定语。“the same”也不一定要与as构成本句型。参见《大学英语语法》P123)

例：I’d like to use the same tool as is used here.（本句中“the same”作tool的定语。as 在从句中作主语。）

the same as 与the same that 有时意义有所区别。但一般情况下可相互替换，如上句可写为：

I’d like to use the same tool that is used here. 与上句意思是一样的。例：This is the same book as I read last week.“这和我上周读的那本书是一样的”

This is the same book that I read last week.“这就是我上周读的那本书。”

由as, as…as, 否定形式为：not so/as…as,引导的状语从句。因为引导状语从句的都是从属连词，因为其不在从句中作成分，因此两个句型中的后面的一个as都是连词，在从句中不作成分。这一点要与上面的as引导的定语从句区别开来。

not so/as…as(本句型中前面的so和as都是副词，后面的as是从属连词，引导比较状语从句。)

例：The teacher did as their teacher told them.“学生们按照老师说的做了。”

The horse is getting old and can not run as fast as it did.(第一个as修饰fast，第二个as为从属连词，引导状语从句。)

She dances as gracefully as her sister.(本句中“her sister”后面省略了“dances”)

(三)倍数的表达：①/…times+ as…+as…②twice/times...+比较级+than…③…times+ the size/height/length/width/weigh/amount等名词+of…

两倍用“twice”，一倍用“as…as…”

例：after the new technique was introduced ，the factory produced twice as many tractors in 1988 as the year before.（第一个句型）

例：Light travels many times faster than sound(travel).（第二个句型）The meeting-room is three bigger than our office.“会议室比我们的办公室大三倍。”（4倍大）

例：Your piece of cake is three times the size of mine(第三个句型)

例：john plays football as well as, if not better than, David.（表示一倍的句型）

“约翰足球踢得如果不比大卫，也和他一样好。”