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as的5种意思及用法

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as的5种意思及用法
as的5种意思及用法
解题思路: as的用法是英语学习中的难点,也是考试的出题点,平时只有在弄清楚用法的基础上多加练习才能取得好的效果。
解题过程:
 一、用作连词的as
  1. 引导时间状语从句,表示“当……的时候”,其用法与when和while类似。例如:As a child (When he was a child), she was sent to six different schools.此用法中as多表示从句与主句动作同时进行,意为“一边……一边……”,一般不与状态动词连用。例如:She sang songs as she did her homework.
  as 还可以表示一动作紧接着另一动作发生,说明另一动作的结果,有“随着……”的含义。例如:As time went by, we found he was an honest man./As he grew older, he lost interest in everything except gardening.
  例1 It wasn’t until nearly a month later________ I received the manager’s reply.
  A. since B. when C. as D. that
  解析:本题的as中与when一起作为干扰项,容易使考生往时间状语从句上思考,事实上本题是强调句,正确选项是D。
  2.引导原因状语从句,表示“由于,因为”,相当于because, 但通常置于句首。例如:
  As he is a qualified doctor, I trust his advice on medical matters.
  例2 _____ modeling business is by no means easy to get into, the good model will always be in demand.
  A. While B. SinceC. AsD. If
  解析:本题中as干扰性很强,很多考生误以为是原因状语从句,但仔细分析不难发现正确答案应是A(while表示“只要”)。
  3.引导让步状语从句,通常可与although或though通用,但语序不同,although或though用于句首,as用于倒装结构。例如:Young as I am, I already know what career I want to follow. /Although(或Though)I am young, I already know what career I want to follow.
  as 表示让步用于倒装结构,通常将从句的表语、状语或动词前置。如果表语有冠词a/an, 需去掉。例如:Great scholar as he is, he is lacking in common sense./Much as I like you, I couldn’t live with you./Try as he would, he couldn’t open the door.
  例3 _____ he has limited technical knowledge, the older worker has a lot of experience.
  A. SinceB. Unless C. AsD. Although
  解析:as 虽然有引导让步状语从句用法,但本题不是倒装结构,故正确答案应是D。
  4.引导方式状语从句,表示“如,像”。例如:When in Rome, do as Romans do./Do to others as you would have others do to you.
  例4 We wanted to get home before dark, but it didn’t quite ________ as planned.
  A. make outB. turn out C. go onD. come up
  解析:本题考查动词词组辨析,题干中的“as planned”给同学们提供了重要信息,答案选B。
   5.固定句型:“主句,as +be/do+主语”表示“也一样”。例如:She’s unusually tall, as are both her parents./He’s a doctor, as was his wife before she had children.
  二、用作介词的as
  1.表示“如,像”。例如:They got united as one man./She spoke of me as her dearest friend.
  2.表示“作为、当作”。例如:As a League member, you should think more of others./After graduating from the college, he firstly worked as a clerk in a big company.
  3.与某些动词搭配,表示“把……当作……”,如:look on…as…, regard…as…, treat…as…, consider…as…, think of…as…, see…as…等。其中consider…as…中的as可以省略。as与famous或known搭配,表示“作为……而出名”。
  例5 Linda worked for the Minnesota Manufacturing and Mining Company, ________ as 3M.
  A. knowingB. known C. being knownD. to be known
  解析:如果熟悉be known as这一短语,运用有关非谓语动词的常识,可选出正确答案B。
  三、用作关系代词的as
  1.引导限制性定语从句,先行词前通常有as, so, such, same等修饰语。例如:He will marry as pretty a girl as he can find./My hometown is no longer the same as it used to be./As many people as are present will be given a present.在此种用法中,同学们要注意与结果状语从句的区别。比如:A: The teacher asked us such a difficult question that none of us could answer it.B: The teacher asked us such a difficult question as none of us could answer.A句为结果状语从句,而B句则是定语从句。2.引导非限制性定语从句,用来指代整个主句(即先行句),表示“这一事实,那一情况”。从句可以位于句首、句中或句末。例如:We stand when the national anthem is played, as is the custom.
  例6 ______ I explained on the telephone, your request will be considered at the next meeting.
  A. When B. After C. As D. Since
  解析:根据句意,选项C是正确答案。as表现的正是本点所讲用法。
  例7 _______ is our belief that improvements in health care will lead to a stronger, more prosperous economy.
  A. AsB. That C. ThisD. It
  解析:本题中的as项干扰性很强,容易误选。实际上句中that引导的应是真正的主语从句,it充当形式主语,故选D。如果将题干中的that换为逗号,则必须选as。
  例8 Danby left word with my secretary ________ he would call again in the afternoon.
  A. whoB. thatC. asD. which
  解析:that引导的从句是word的同位语,本题应选B。as无此用法,起干扰作用。
  四、用作副词的as
  修饰形容词或副词,表示程度,意为“同样地”。例如:He swims fast, but I swim just as fast. 但它通常构成表示比较的结构“as…as…”,“not as…as…”。此结构中第一个as是副词,第二个as是连词。否定结构中的副词as可以由so代替。as…as possible /one can也属于此用法。例如:It is generally believed that teaching is as much an art as it is a science./The movie was not as good as I had expected./I play tennis as well as him .
  五、用在习语中的as
  由as构成的习语很多,常见的有:as soon as “一……就”,引导时间状语从句;as/so long as “只要”引导条件状语从句;as if/though “好像,仿佛”,引导方式状语从句或表语从句;as to/ as for “至于,就……而言”;as much/many as“多达……”;as/so far as “就……的限度”;as a result,as a result of “(由于……的)结果”;as a matter of fact“事实上”;as well “也、还”;A as well as B“不但A而且B”;as it is“照现状看,看样子”,等等。这些习语在高考中可能经常遇到,在高考题中有的作为正确选项,有的作为干扰项,有的出现在题干,值得同学们认真掌握。例如:
  例9 I would like a job which pays more, but ______ I enjoy the work I’m doing at the moment.
  A. in other wordsB. on the other hand C. for one thing D. as a matter of fact
  解析:选项D极具干扰意义,但进一步研读会发现本题中的两个分句表达了一件事的两个对立面,故选B。
  例10 ——People should stop using their cars and start using public transport.
  ——______. The roads are too crowded as it is.
  A. All right B. Exactly C. Go aheadD. Fine
  解析:本题选项中虽没有as内容,但题干中的as it is却是解题的关键信息,正确选项为B。
  例11 Maggie has been fortunate to find a job she loves and, _____, she gets well paid for it.
  A. sooner or later B. what’s more C. as a result D. more or less
  解析:本题后一个分句不表示结果,而是递进,故选B,而不是C。
  例12 The winter of 1990 was extremely bad. _______ most people say it was the worst winter of their lives.
  A. At last B. In factC. In a wordD. As a result
  解析:选项D. As a result起干扰作用,正确选项为B。