介词as的用法.ppt

1、AS的用法,介词,副词,连词,关系代词,关系副词,1.表示好像。 如:Hedressedasapoliceman. 2.表示作为当作。 如：Ifoundajobasaguide. 3.当某人是某身份时。 如：Asachild,shewassenttoabroad.,4.as引导的介词短语大多用作状语,as译为“作为”;少数情况可引起宾语补足语。如:AsaPartymember,Illtaketheleadineverything.(状语) Sheworksasamodel.(状语) Shehasmeasoneofherbestfriends.(引起宾语补足语),介词,副词,连词,关系代词,关系

2、副词,1表示与-等同。如：Thisdressistwiceasexpensiveasthatone. 2像，如等。如：Asbefore,heremainedunmoved.,介词,副词,连词,关系代词,关系副词,常用来连接主句和状语从句,1)as引导行为方式状语从句时,意为“如同”“按照的方式(样子,办法)”这种从句常位于主句之后 例如: You must try to hold the tool as I do. 你必须像我这样拿工具 Leave the things as they are. 别动这些东西 We must do as the Party tells us (to do).

3、我们必须按照党的指示办事 2)(just) asso结构中位于句首，这时as从句带有比喻的含义，意思是“正如”，“就像”，多用于正式文体 。 例如： Always do to the others as you would be done by. As water is to fish, so air is to man. Just as we sweep our rooms, so we should sweep backward ideas from our minds.,as表示原因引导原因状语从句，常与because，for，since辨析。 because 表示直接原因，常用来回答w

4、hy的提问；since因为， 既然，表示显然的或已知的理由；for因为，由于，表示附加的或 推断的理由，不放句首；as由于，鉴于，从句说明原因，主句说 明结果，为常用词。 1 Jenny was very sad over the loss of the photos she had shot at Canada，_this was a memory she especially treasured. A. as B. if C. when D. where 2 A man cannot smile like a child，_ a child smiles with his eyes，whi

5、le a man smiles with his lips alone. A. so B. but C. and D. for 3 _ all of you knows the news，I wont tell you about it again. A. For B. Since C. When D. Unless,as引导让步状语从句，译为“虽然，尽管”。 as作此用法时，常与though，although比较。as 引导的让步状语从句，必须倒装，把名词（省略冠词）、作表语的形容词、副词或动词原形提到句首，用法与though相似，不同的是though引导的让步状语从句可以倒装，可以不倒装；

6、although引导的让步状语从句不倒装，且多置于句首。 如 Child as he is，he knows a lot.(名词提到as之前，且省去冠词)。 Much as he likes the bicycle，he wont buy it.(副词much提到句首) Improbable as it seems，its true.(作表语的形容词提到句首) Object as you may，Ill go.（情态动词后的动词原形提到句首）,当as引导让步状语从句时，句子的倒装语序有以下三种形式：,(1). 形容词或副词+as+主语+连系动词be或实义动词。例如： Rich as he is

7、, he never spends a cent on clothes. 虽然他很富有，但他从不花一分钱在衣服上。 Much as I admire his courage, I dont think he acted wisely. 我虽然佩服他的勇气，但我认为他这样做是不聪明的。,(2). 名词+as+主语+连系动词be (注意句首的名词不带冠词)。 例如： Child as he is, he knows a lot. 尽管他是个孩子，但懂很多事情。Boy as he was, he was chosen king. 尽管他还是个孩子，但却被立为国王。 (3). 实义动词+as+主语+助

8、动词如果没有助动词，则要加上一个do (does或did)。例如： Try as he may, he never succeeds. 尽管他很努力，但总是不成功。 Change your mind as you will, you will gain no additional support. 即使你改变主意，你也不会得到另外的支持。,as引导比较状语从句,用于“as.as.或 not so/ as.as.”中,前一个as是副词,后一个as是连词，意为“如(不如)一样”。如: (1). You hate her as much as I (=as I hate her). (2). I d

9、ont speak English so/ as well as he does.注意：句中连词as后面的代词实际是省略了与主句相同的部分，即例(1)可以写成You hate her as much as I hate her. 如果很明显就能看出所省略的部分，意义不会含糊不清时，在口语中也可以用代词的宾格形式。例：At your age you cant expect to play football as well as me (= as I do).但例(1)就不能改I为me，改后意思就变为：You hate her as much as you hate me. 你恨她像恨我一样深;而

10、原句的意思为：你恨她像我恨她一样深。,as可表示时间，译为“当的时候”，引导时间状语从句。as作此用法时，常与when，while比较。when后的时间状语从句的谓语既可是延续性动词，又可是短暂性动词，而while后必须是延续性动词；as侧重于主句与时间状语从句的两个动作同时发生，常译为“一边一边”。 如 ：WhenWhile he worked in the factory，he learned a lot from the workers. 当他在那个工厂工作的时候，他从工人那儿学到了很多。（work为延续性动词） He jumped up when she called. 当她打电话来的

11、时候，他跳了起来。（call为短暂性动词）,介词,副词,连词,关系代词,关系副词,As作关系代词时可引导：,1引导限制性定语从句，用在“suchas”,“the sameas”，“asas”等结构中，常译作“像一样的人(或物)”，“凡是的人(或物)”。例eg：He wished to be such a man as Lei Feng was 他曾希望做一个像雷锋那样的人。My hometown is no longer the same as it was 我的家乡再也不像过去一样了。,注意such.as.与such.that.的区别,such.as. 引导的是定语从句，as后的定语从句缺少

12、主语或宾语等句子成分，而such.that.为结果状语从句，that后必须是一个完整的句子，意为“如此以至于”。 如: The teacher set such a difficult problem as none of us worked out. (as后为定语从句，先行词problem在定语从句中充当work out的宾语) The teacher set such a difficult problem that none of us worked it out. (that后为一个完整的句子，句意为老师问了一个如此难的问题，以至于我们都答不出来),the same.as.和the

13、same.that.的区别,the same.as.“相同的”，指的是同一类，而非同一个；the same.that.“同样的”，指的是同一个。 如 :This is the same watch as I bought in the department store. 这块表跟我在商店里买的一样。（指的是同一类，并非同一块） This is the same watch that I lost in the hotel yesterday. 这就是我昨天丢在旅店的表。（指同一块表）,2引导非限制性定语从句，用来指代它前面的整个句子(即先行句)，意思是“正如，这一点”。 （动词常为know,

14、see, expect, point out, etc.）这个分句可以位于句首、句中或句末。eg：As is well known，oceans cover more than 70 of the earth我们知道，海洋占地球面积的百分之七十以上。(as作主语） As we all know, smoking is harmful to ones health . (as 作宾语),as引导非限定性定语从句， 常用于下列结构： as we all knowas is known to us all 众所周知 as is hopedexpectedannounced. 正如希 望预料宣布的那样

15、 as is often the case 情况通常都是如此,as和which都引导非限定性定语从句，用来修饰或限定整个主句的内容，有时可以互换。e.g. 1.He failed in the English examination, as/which his parents expected.2.He is a Beijinger,as/which I know from his accent. 但在下列情况下，as和which不可互换,但在下列情况下，as和which不可互换,七.as 既可指前面提到的事，又可指后面提到的事；which只能指前面提到的事。E.g.1.As is known, well see a film this afternoon.(指后面的事）2.Sam has been