作者：秦  振

摘要：as在高中英语中是一个使用频率很高的单词，又是重要考点，它有三种词性，并且句法及语法功能纷繁复杂。本文以as的三类词性（介词，副词，连词）为顺序，分别讲述其在不同词性下的各种用法。最后，本文还将讲述as的一些常见固定词组和as作关系代词在定语从句中的用法。

关键词：as；词性；比较结构；关系代词；定语从句；状语从句；倒装结构
    

一、as用作介词，后接名词，此时as意义为“作为……”，它用来指所提到的人或物的性质，用途，身份。

请注意：as后面所接的名词的单复数应该与它所指的人或物的单复数一致。

如：As a student, he is hardworking.

   As students, they are hardworking.

高考真题例句：

(2005湖南) We wentto Canada to travel and my cousin acted as our guide.

(2006湖南) As the busiest woman in Norton, she madeit her duty to look after all

the other people’s affairs in that town.

(2007湖南) Polarbears live mostly on sea ice, which they use as a platform for hunting seals.

二、as用作副词，用于比较结构“as + 形容词或副词的原级 + as”中, 表示两者或两方面的比较，也可以显示所提到的人或物的程度。 
(北师大版高中英语必修一第12页) It can get as cold as minus 40 or 50 degrees at night.

(北师大版高中英语必修三第8页) There were as many as 10,000 Vikings living in Iceland.

(北师大版高中英语必修三第12页) Some fish canproduce sounds almost twice asloud as your speaking voice!

(北师大版高中英语必修三第12页) It is not as big as a fly in your house!

as用于比较结构，而比较结构有多种变化形式。

如：My house is 3times as large as yours.

       =Myhouse is 3 times larger than yours.

       =Myhouse is 3 times the size of yours.

在以上的结构变化形式中，要注意倍数词必须置于“as + 形容词或副词的原级 + as” 之前。

高考真题再现（斜体字选项为正确答案，下同）：

(2005湖北) What atable! I’ve never seen such a thing before. It is       it is long.

   A. half not as wideas                            B. wide not as half as

       C. not half as wide as                             D. as wide as not half 

(2005上海) A roughestimate, Nigeria is__________ Great Britain.

   A. three times the size as                      B. the size three times of

C. three times as thesizeof                    D. three times the size of

(2005安徽) John isthe tallest boy in the class, ____________ according to himself.

A. five foot eight astall as            B.as tall as five foot eight

C. as five foot eighttall as            D. as tall five foot eight as

分析：此题中的as…as 结构并不是用于两者间的比较，而是显示所提到的人(即John) 的程度，说明其具体有多高。

(2010上海) Inancient times, people rarely travelled long distances and most farmers

only travelled      _____   the local market.

   A.longer than      B.more than        C. as much as         D.as far as

分析：此题中的as…as 结构并不是用于两者间的比较，而是显示所提到的事物(即distance) 的程度，说明其具体有多远。

(2006全国Ⅱ卷) — Did you take enough money with you?

— No, I needed_______ I thought I would.

A. not so muchas    B. as muchas    C. muchmore than   D. muchless than

(2008浙江) I likethis jacket better than that one, but it costs almost three times______.

A. as much           B.as many         C. so much          D. so many

(2009江西)According to statistics, a man is more than twice as likely to die of skin

cancer _________ a woman.

  A.than               B.such              C.so             D. as

另外，还有一些形式上是“as + 形容词或副词的原级 + as” 结构的固定词组，他们并不是或并不一定是表示两者之间的比较。这些词组中常见的有：as soon as; as soon as possible; as … aspossible; as well as; as/so long as; as good as

1. as soon as 表示“一……就……”

( 2005北京) As soon as he comes back, I’ll tell him when youwill come and see him.

2. as soon aspossible 表示 “尽可能地早”

as … as possible 表示“尽可能……”

(2005湖北) If Icould plan to do anything I wanted to, I’d like to go to Tibet and

travel through asmuch of it as possible.

(2006全国Ⅱ卷) We hope that as many people as possible can join us for the picnic tomorrow.

(2008陕西) Themessage is very important, so it is supposed to be sent as soon as possible.

3. as well as 有两种用法：

3.1 as well as 表示“和……一样好”，属于比较结构，well 是副词原级。

(2007陕西) Thoughhe started late, Mr. Guo played the piano aswell as, if not better than, Miss Liu.

3.2 as well as 还表示“和……”，此时，应注意句中的主谓一致问题和该结构其后的动词形式问题。

(2005江苏) Unlikewatching TV, reading is a highly active process for it requires attention as well as memory and imagination.

(2006辽宁) Thefather as well as his three children goes skating on the frozen river everySunday afternoon in winter.

(2007上海) AIDScontrol and prevention is a challenge to China as well as the whole world.

(北师大版高中英语必修一第18页) Normally, severaldifferent drinks such as tea, hot chocolate or a soft drink like orange juicewill be served as well as coffee. Merchants and bankers wentto coffeehouses to do their business aswell as to drink coffee.

3.3 as well 表示“也”，用于句尾。

(2010福建) — Inthis day and age, women can have children and jobs as well.

— I can’t agree more.It’s great to have the two combined.

3.4 might (just) as well 表示“不妨……”，“还是……的好”

如：We planedto go climbing, but since it is raining now, we might just as well stay

home watching TV.  

4. as/so long as 有两种用法：

4.1 as long as 表示“和……一样长”，long是形容词原级。

如：This road is as long as that one.

4.2 as/so long as 表示“只要……”，后接条件状语从句。

(2005重庆) Daddydidn't mind what we were doing, aslong as we were together,

having fun.

(2009北京) You mayuse the room as you like solong as you clean it upafterwards.

(2008全国I卷) — Have you got any idea for the summervacation?

— I don’t mind wherewe go as long as there’s sun, sea and beach.

5. as good as有两种用法：

5.1 as good as 表示“和……一样好”，good 是形容词原级。

如：Your writing is as good as his.

5.2 as good as 表示“几乎……”

如：The decorating is asgood as finished --- I justneed to finish off the painting.

三、as用作连词，用于连接句子。

1. as 表示“因为……”，相当于because，引导原因状语从句。

(北师大版高中英语必修一第36页) As it is in early summer, it marks thebeginning of the hottest season of the year.

(2006广东) Jennywas very sad over the loss of the photos she had shot at Canada, _______ thiswas a memory she especially treasured. 

A. as             B.if             C.when             D. where

(2006上海) Someexperts think that language learning is much easier for children as their tongues are more flexible.

2. as 表示“当……时”或“随着……”，相当于while，引导时间状语从句。

(北师大版高中英语必修一第23页) As Yang Liwei returned into the earth’satmosphere, helicopters were flying to where he would land, ready to collecthim.

(2006北京) — Wheredid you put the car keys?

 — Oh, I ________ I put them on the chair because the phonerang as I ______ in.

   A.remembered; come           B.remembered; wascoming                   

   C.remember; come             D.remember; was coming

(2007湖南) As the years passed, many occasions ----birthdays, awards, graduations ---- were marked with Dad’s flowers.

(2009全国I卷) The children allturned to look at the famous actress as she entered the classroom.

3. as 表示“尽管……”，相当于though，用于倒装结构“形容词/副词/动词/名词（名词前不用冠词）+ as + 主谓部分”中，引导让步状语从句。

(2005广东)________________, Carolina couldn't get the door open.

    A.Try as she might                          B.As she might try

    C.She might astry                          D. Might she as try

(2005重庆)_____________, he talks a lot about his favorite singers after class.

A. A quiet student as he may be           B.Quiet student as he may be

C. Be a quiet student as he may           D. Quietas he may be a student

(2007重庆)______________, his idea was accepted by all the people at the meeting.

A. Strange as mightitsound                                  B. As it might sound strange

C. As strange itmight sound                                 D.Strange as it might sound

4. as 表示“正如……”，用于描述某事发生或完成的方式，引导方式状语从句或比较状语从句或定语从句。

(2005浙江) _______I explained on the phone, your request will be considered at the

next meeting.

A. When          B.After              C.As             D.Since

(2005天津) TheBeatles, ________ many of you are old enough to remember, came from Liverpool.

A. what            B.that            C. how            D. as

(2008福建) — Who should be responsible for theaccident?

 — The boss, not the workers. They just carried out the order_____.

  A. astold          B.as are told        C. as telling        D. as they told

分析：选项A的完整形式应该是as theywere told。

(2009天津) I travelto the Binhai New Area by light railway every day, _____ do

many businessmen who live in downtown Tianjin.

   A.as             B.which          C.when           D.though

(2012安徽) A lot oflanguage learning, _____ has been discovered, is happening in the first year oflife, so parents should talk much to their children during that period.

   A.as            B.it             C.which            D. this

四，as的常见固定词组：

1. as if/though “好像……”， “似乎……”

注意：as if/though 后接句子，如果所接句子表示虚拟，则用虚拟语气；如果所接句子表示事实或可能性，则不用虚拟语气。

如：He earns just a littleeveryday, but he spends money as if/though he were a millionaire.

(2010陕西) —What’sthe noise? It sounds as if it comes from upstairs.  

 —I don’t think so. It must be the window-cleaner working nextdoor.  

(2006全国I卷) Eliza rememberseverything exactly as if it _________ yesterday.

A. washappening       B.happens      C.has happened       D.happened

2. as to “关于……”  用于引出话题或谈论到某话题。

如：He wasuncertain as to which road to take.

(2009安徽) __ ____     a certain doubt among thepeople as to the practical value of theproject.

     A.It has        B. They have       C. Itremains       D.There remains

3. as follows “如下……” 位于be动词之后，用于例举。

如：The winners are asfollows ---- Woods, Smith andCassidy.

4. as it is “已经，早已”，相当于already，一般位于句尾，与完成时连用。

如：I'm not buying the children anything else today. I've spent fartoo much money as it is.

(2005浙江) — Peopleshould stop using their cars and start using public transport.

— Exactly. The roadsare too crowded as it is.

5. as a whole “总体上”，是副词短语，在句中作状语。

如：The population asa whole is getting healthier.

6. as a matter offact “事实上，实际上”

如：As a matter of fact, he is not a doctor but a lawyer.

(2007安徽) — Didn'tyou have a good time at the party?

 — Of course I did. Asa matter of fact, I had such fun that time seemed to go by soquickly. 

7. as a result “因此……”，后接结果状语从句。

  as a result of…“由于……”，后接名词或名词词组，表示原因。

如：There is a great drop in sales, asa result, profits have declined.

Profits have declined as a result of the recent drop in sales.

(2005江西) Myfriend Martin was very sick with a strange fever; ______________,

he could neither eat nor sleep.

     A.as a result             B. afterall               C. anyway               D. otherwise

8. as/so far as Iknow; as/so far as I'm concerned; as/so far as I can tell “在我看来”，“据我所知”

如: He isn't coming today, asfar as I know.

She can come whenevershe likes, as far as I'mconcerned.

There's been nochange, as far as I can tell.

(2006江西) —Michael was late for Mr. Smith’s oral class this morning.

 — How come? Asfar as I know, he never came late to class.

9. so as to... “为了……”，相当于in orderto, 后接动词原形作目的状语。

如：I always keep fruit in the fridge so as to keep insects off it.

(2005辽宁) Allthese gifts must be mailed immediately ________________ in time for Christmas.

        A. in order to havereceived            B.in order to receive

C. so as to bereceived                D.so as to be receiving

10. such as to… “……是如此，以至于……”，后接动词原形作结果状语。

(2008江西) MyEnglish teacher’s humor was _____________ make every student burst intolaughter.

A. so asto         B.such as to        C.such that         D. so that

11. so + 形容词或副词的原级+ as to… “如此的/地……以至于……”，后接动词原形作结果状语。

如：He is so brave (ahero) as to win everyone’srespect.

    He did so bravely in the war as to win everyone’s respect.

(2009安徽) — Couldyou be so kind as to close the window?

 — With pleasure.

12. such + 名词或名词词组+ as to… “如此的……以至于……”，后接动词原形作结果状语。

如：He is such abrave hero as to wineveryone’s respect.

五、as 作关系代词用于定语从句。

1. such + 名词或名词词组 + as + 定语或定语从句部分。该结构中的名词或名词词组是先行词，as是关系代词。该结构中的such可以转换成so.

如：He is such abrave hero as everyonerespects.

= He is so brave a hero as everyone respects.

(2010重庆)Everything comes with a price; there is no suchthing as free lunch in the world.

注意：要区分该结构与以下结构：

1.1. such + 名词或名词词组 + as + 例举部分，也可以写成：名词或名词词组 + such + as + 例举部分，该结构用于举例说明。

(2010四川) Such poets as Shakespeare are widely read，of whose works，however，some are d