as

prep.

1. 像；如同
   used to describe sb/sth appearing to be sb/sth else
   1. They were all dressed as clowns.
      他们都打扮成小丑。
   2. The bomb was disguised as a package.
      炸弹伪装成一个包裹。
2. 作为；当作
   used to describe the fact that sb/sth has a particular job or function
   1. She works as a courier.
      她的职业是导游。
   2. Treat me as a friend.
      要把我当作朋友。
   3. I respect him as a doctor.
      我尊敬他这个医生。
   4. You can use that glass as a vase.
      你可以把那个玻璃杯当作花瓶用。
   5. The news came as a shock.
      消息传来，令人震惊。
   6. She had been there often as a child (= when she was a child) .
      她小时候常去那里。

adv.

1. （比较时用）像…一样，如同
   used when you are comparing two people or things, or two situations
   1. You're as tall as your father.
      你和你父亲一样高。
   2. He was as white as a sheet.
      他面无血色。
   3. She doesn't play as well as her sister.
      她演奏得不如她姐姐。
   4. I haven't known him as long as you (= as you have known him) .
      我认识他的时间没有你长。
   5. He doesn't earn as much as me.
      他挣的钱比我少。
   6. He doesn't earn as much as I do.
      他挣的钱不如我多。
   7. It's not as hard as I thought.
      这没有我想象的那么困难。
   8. Run as fast as you can.
      你尽量快跑。
   9. We'd like it as soon as possible.
      我们希望越快越好。
2. （指事情以同样的方式发生）和…一样
   used to say that sth happens in the same way
   1. As always, he said little.
      他和平时一样，少言寡语。
   2. The ‘h’ in honest is silent, as in ‘hour’.
      honest中的h与hour中的h一样都不发音。

conj.

1. 当…时；随着
   while sth else is happening
   1. He sat watching her as she got ready.
      他一直坐着看她准备停当。
   2. As she grew older she gained in confidence.
      随着年龄的增长她的信心增强了。
2. 照…方式
   in the way in which
   1. They did as I had asked.
      他们是按照我的要求做的。
   2. Leave the papers as they are.
      别去动那些文件。
   3. She lost it, just as I said she would.
      我就说了吧，她把它丢了。
3. 因为；由于
   used to state the reason for sth
   1. As you were out, I left a message.
      你不在，所以我留了一张字条儿。
   2. She may need some help as she's new.
      她是新来的，可能需要一些帮助。
4. 正如；如同
   used to make a comment or to add information about what you have just said
   1. As you know, Julia is leaving soon.
      你是知道的，朱莉娅马上要离开了。
   2. She's very tall, as is her mother.
      她个子很高，和她母亲一样。
5. 尽管；虽然；即使
   used to say that in spite of sth being true, what follows is also true
   1. Happy as they were, there was something missing.
      尽管他们很快乐，但总缺少点什么。
   2. Try as he might (= however hard he tried) , he couldn't open the door.
      他想尽了办法也没能打开门。

CONJUNCTION AND PREPOSITION USES 连词和介词用法

1. CONJ-SUBORD （表示两件事情同时发生）当…的时候，在…的同时
   If something happens as something else happens, it happens at the same time.
   1. Another policeman has been injured as fighting continued this morning...
      今早又有一名警员在冲突中受伤。
   2. All the jury's eyes were on him as he continued...
      在他继续陈述的时候，全体陪审员的目光都集中在他身上。
   3. The play started as I got there.
      我到那里的时候演出开始了。
2. PHR-CONJ-COORD 像…一样
   You use the structure as...as when you are comparing things.
   1. I never went through a final exam that was as difficult as that one...
      我从来没有碰到过像那次那么难的期末考试。
   2. There was no obvious reason why this could not be as good a film as the original.
      找不出明显的理由来解释为什么这部片子拍得不如原先的好。
   3. As is also a conjunction.
      
   4. Being a mother isn't as bad as I thought at first!...
      做母亲并不像我一开始想的那样糟！
   5. I don't think he was ever as fit as he should have been.
      我认为他本该更健康的。
3. PHR-CONJ-COORD （强调数量）多达，只有
   You use as...as to emphasize amounts of something.
   1. You can look forward to a significant cash return by saving from as little as £10 a month...
      只要每个月存下区区10英镑，你就有希望得到相当可观的现金收益。
   2. She gets as many as eight thousand letters a month.
      她一个月里收到的信件多达8,000封。
4. PREP 作为；当作
   You use as when you are indicating what someone or something is or is thought to be, or what function they have.
   1. He has worked as a diplomat in the US, Sudan and Saudi Arabia...
      他曾任驻美国、苏丹和沙特阿拉伯的外交官。
   2. The news apparently came as a complete surprise...
      这个消息显然让人大吃一惊。
   3. I had natural ability as a footballer.
      我天生就是当足球运动员的料。
5. PREP 还是…的时候
   If you do something as a child or as a teenager, for example, you do it when you are a child or a teenager.
   1. She loved singing as a child and started vocal training at 12.
      她从小就喜欢唱歌，12岁开始了声乐训练。
6. CONJ-SUBORD 同样地；一样地；像…一样
   You use as to say how something happens or is done, or to indicate that something happens or is done in the same way as something else.
   1. I'll behave toward them as I would like to be treated...
      我会以希望别人对待我的方式来对待他们。
   2. Today, as usual, he was wearing a three-piece suit...
      像往常一样，他今天穿的是三件套。
   3. The book was banned in the US, as were two subsequent books.
      这本书在美国遭禁，随后出版的两本也是一样。
7. PREP 因为;作为（结果）
   You use as in expressions like as a result and as a consequence to indicate how two situations or events are related to each other.
   1. As a result of the growing fears about home security, more people are arranging for someone to stay in their home when they're away...
      因为越来越担心住宅安全，更多的人在出门的时候会在家中留人。
   2. In this changing business environment, different demands are being placed on employees. As a consequence, the education system needs to change.
      在当今变幻莫测的商业环境下，员工被提出各种不同的要求。因此，教育体系有必要随之改变。
8. CONJ-SUBORD （引导短从句）正如，就像
   You use as to introduce short clauses which comment on the truth of what you are saying.
   1. As you can see, we're still working...
      如你所见，我们仍在工作。
   2. We were sitting, as I remember, in a riverside restaurant.
      我记得我们当时是坐在一个河畔的餐馆里。
9. CONJ-SUBORD 因为；由于
   You can use as to mean 'because' when you are explaining the reason for something.
   1. They are regularly sent booklets about personal safety, but they barely read them as they have so much paperwork to deal with...
      他们经常会收到关于人身安全问题的宣传册，但因为大量文案工作缠身，他们几乎无暇阅读。
   2. Enjoy the first hour of the day. This is important as it sets the mood for the rest of the day.
      好好享受每天的第一个小时。这之所以重要是因为它会决定你一整天的心情。

You can use as, because, since, or for to give an explanation for something. Because is the commonest of these, and is used when answering a question beginning with 'why?'.You can use as or since instead of because to introduce a clause containing a reason for something, especially in writing. ...a note about The National Portrait Gallery, as the word 'Gallery' can be misleading... Since the juice is quite strong, you should always dilute it. In stories, for is sometimes used to explain or justify something. He seemed to be in need of company, for he suddenly went back into the house. Note that because is a conjunction, and is used to link two ideas within one sentence. I'm unsocial, because of my deafness.
as, because, since 和 for 都可以表示“因为”。because 最常用，往往用来回答以why开头的疑问句。as 和 since 尤用于书面语中，可以代替 because 引导原因从句。如：a note about The National Portrait Gallery, as the word ‘Gallery’can be misleading（对 The National Portrait Gallery 的注释，因为 Gallery 一词易产生歧义），Since the juice is quite strong, you should always dilute it（这果汁很浓，你应该把它冲淡一些）。在讲故事时，for 用来解释或证明某事。如：He seemed to be in need of company, for suddenly he went back into the house （他看上去需要有个伴，因为他突然又回到屋里去了）。注意，because是连词，用于连接一个句子中的两个部分，如：I'm unsocial, because of my deafness （由于失聪，我不喜欢社交）。

10. PHRASE 可以说;在某种程度上
    You say as it were in order to make what you are saying sound less definite.
    1. I'd understood the words, but I didn't, as it were, understand the question.
       字面的意思我懂了，但是可以说我并不能理解这个问题。
11. PHRASE 事实上，实际上（表示实际情况和可能情况的对比）
    You use expressions such as as it is ,as it turns out, and as things stand when you are making a contrast between a possible situation and what actually happened or is the case.
    1. I want to work at home on a Tuesday but as it turns out sometimes it's a Wednesday or a Thursday.
       我想周二在家工作，但实际上有时却是周三或是周四。
12. as against → see: against

USED WITH OTHER PREPOSITIONS AND CONJUNCTIONS 与其他介词或连词连用

1. PREP-PHRASE 至于…
   You use as for and as to at the beginning of a sentence in order to introduce a slightly different subject that is still connected to the previous one.
   1. I feel that there's a lot of pressure put on policemen. And as for putting guns in their hands, I don't think that's a very good idea at all.
      我觉得给警员的压力太大了。至于让他们佩枪，我并不认为是一个明智之举。
2. PREP-PHRASE 关于…
   You use as to to indicate what something refers to.
   1. They should make decisions as to whether the student needs more help...
      他们应该决定学生是否需要更多的帮助。
   2. Andy sat down at the table and inquired as to what the problem was.
      安迪在桌边落座，询问出了什么问题。
3. PREP-PHRASE 在…时；从…起；自…始
   If you say that something will happen as of, or in British English as from, a particular date or time, you mean that it will happen from that time on.
   1. The border, effectively closed since 1981, will be opened as of January the 1st...
      实质上从1981年就已关闭的边境将于1月1日开放。
   2. She is to retire as from 1 October.
      她将于10月1日退休。
4. PHR-CONJ-SUBORD 好像；仿佛
   You use as if and as though when you are giving a possible explanation for something or saying that something appears to be the case when it is not.
   1. Anne shrugged, as if she didn't know...
      安妮耸了耸肩，好像她并不知晓。
   2. He burst into a high-pitched laugh, as though he'd said something funny.
      他突然放声大笑，好像讲了什么好笑的事似的。

1. Another policeman has been injured as fighting continued this morning
   今早又有一名警员在冲突中受伤。
2. All the jury's eyes were on him as he continued
   在他继续陈述的时候，全体陪审员的目光都集中在他身上。
3. The play started as I got there.
   我到那里的时候演出开始了。
4. I never went through a final exam that was as difficult as that one
   我从来没有碰到过像那次那么难的期末考试。
5. There was no obvious reason why this could not be as good a film as the original.
   找不出明显的理由来解释为什么这部片子拍得不如原先的好。
6. You can look forward to a significant cash return by saving from as little as £ 10 a month
   只要每个月存下区区10英镑，你就有希望得到相当可观的现金收益。
7. She gets as many as eight thousand letters a month.
   她一个月里收到的信件多达8,000封。
8. He has worked as a diplomat in the US, Sudan and Saudi Arabia
   他曾任驻美国、苏丹和沙特阿拉伯的外交官。
9. The news apparently came as a complete surprise
   这个消息显然让人大吃一惊。
10. I had natural ability as a footballer.
    我天生就是当足球运动员的料。
11. She loved singing as a child and started vocal training at 12.
    她从小就喜欢唱歌，12岁开始了声乐训练。
12. I'll behave toward them as I would like to be treated
    我会以希望别人对待我的方式来对待他们。
13. Today, as usual, he was wearing a three-piece suit
    像往常一样，他今天穿的是三件套。
14. The book was banned in the US, as were two subsequent books.
    这本书在美国遭禁，随后出版的两本也是一样。
15. As a result of the growing fears about home security, more people are arranging for someone to stay in their home when they're away
    因为越来越担心住宅安全，更多的人在出门的时候会在家中留人。
16. In this changing business environment, different demands are being placed on employees. As a consequence, the education system needs to change.
    在当今变幻莫测的商业环境下，员工被提出各种不同的要求。因此，教育体系有必要随之改变。
17. As you can see, we're still working
    如你所见，我们仍在工作。
18. We were sitting, as I remember, in a riverside restaurant.
    我记得我们当时是坐在一个河畔的餐馆里。
19. They are regularly sent booklets about personal safety, but they barely read them as they have so much paperwork to deal with
    他们经常会收到关于人身安全问题的宣传册，但因为大量文案工作缠身，他们几乎无暇阅读。
20. Enjoy the first hour of the day. This is important as it sets the mood for the rest of the day.
    好好享受每天的第一个小时。这之所以重要是因为它会决定你一整天的心情。
21. I'd understood the words, but I didn't, as it were, understand the question.
    字面的意思我懂了，但是可以说我并不能理解这个问题。
22. I want to work at home on a Tuesday but as it turns out sometimes it's a Wednesday or a Thursday.
    我想周二在家工作，但实际上有时却是周三或是周四。
23. I feel that there's a lot of pressure put on policemen. And as for putting guns in their hands, I don't think that's a very good idea at all.
    我觉得给警员的压力太大了。至于让他们佩枪，我并不认为是一个明智之举。
24. They should make decisions as to whether the student needs more help
    他们应该决定学生是否需要更多的帮助。
25. Andy sat down at the table and inquired as to what the problem was.
    安迪在桌边落座，询问出了什么问题。
26. The border, effectively closed since 1981, will be opened as of January the 1st
    实质上从1981年就已关闭的边境将于1月1日开放。
27. She is to retire as from 1 October.
    她将于10月1日退休。
28. Anne shrugged, as if she didn't know
    安妮耸了耸肩，好像她并不知晓。
29. He burst into a high-pitched laugh, as though he'd said something funny.
    他突然放声大笑，好像讲了什么好笑的事似的。
30. It sounds as if you have grown apart from Tom.
    听起来好像你和汤姆之间产生了隔阂。

  although as though【导航词义：虽然，尽管】

  although conj. 尽管，虽然

〔辨析〕通常置于句首并用于正式场合，不能像 though 那样用于省略句或引出倒装语序的让步状语从句。

  as conj. 尽管，虽然

〔辨析〕作此义解时，只用于倒装语序结构中，语气强于 although 和 though。

  though conj. 虽然，尽管

〔辨析〕在文体上不如 although 正式，常用于省略句，或引出倒装语序的让步状语从句。

  because as for since【导航词义：因为，由于】

  because conj. 因为

〔辨析〕语气最强，表示因果关系，通常用来回答由 why 引导的疑问句。由 because 引导的分句置于句首时，须用逗号与主句隔开，置于句末时则不用隔开。

  as conj. 因为，由于

〔辨析〕如果所述理由是明显的或者已知的，则用 as 较 because 更为合适。

  for conj. 〈正式〉因为

〔辨析〕for 属于并列连词，由它引导的分句表示补充说明性的理由，通常只能置于句末，且必须用逗号与前面的分句隔开。

  since conj. 因为，既然

〔辨析〕当所述原因是已知的客观事实或被当作推断的理由时用 since，语气略强于 as。

  when as while【导航词义：当…时】

  when conj. 在…时，当…时

〔辨析〕所引导的状语从句中，谓语可以是延续性动词，也可以是瞬时动词，其动作既可以和主句的动作同时发生，也可以在主句的动作之前或之后发生。

  as conj. 当…时，（正当）…的时候

〔辨析〕引导状语从句时，侧重指从句中的动作与主句中的动作同时发生或同时进行，一般持续时间不长，其谓语可以是延续性动词，也可以是瞬时动词。

  while conj. 当…时，在…期间

〔辨析〕指在某事发生之际或发生的过程中，另一事又发生。所引导的状语从句中，谓语应为延续性动词，而不用瞬时动词，强调其动作与主句中的动作同时发生，但持续时间一般较长；有时也可指主句的动作在从句的动作过程中发生。

conj.

as against sth

• 与…相对照；和…相比较
  in contrast with sth
  1. They got 27% of the vote as against 32% at the last election.
     这次选举他们得了27%的票，而上次他们得了32%。

as and when

• （用于在特定条件下才会发生的事情）将来…时，到时候
  used to say that sth may happen at some time in the future, but only when sth else has happened
  1. We'll decide on the team as and when we qualify.
     将来我们具备了条件时就会决定成立这个队。
  2. I'll tell you more as and when (= as soon as I can) .
     我一有可能就会告诉你更多情况。

as for sb/sth

• 至于；关于
  used to start talking about sb/sth
  1. As for Jo, she's doing fine.
     至于乔，她现在日子过得不错。
  2. As for food for the party, that's all being taken care of.
     关于聚会要用的食物，都在置办当中。

as from…/as of…

• （指起始时间或日期）自…起
  used to show the time or date from which sth starts
  1. Our fax number is changing as from May 12.
     我们的传真号码自5月12日起更改。

as if/as though

• 似乎；好像；仿佛
  in a way that suggests sth
  1. He behaved as if nothing had happened.
     他表现得若无其事。
  2. It sounds as though you had a good time.
     听起来你好像过得挺愉快。
  3. It's my birthday. As if you didn't know!
     今天是我的生日。你好像不知道似的！
  4. ‘Don't say anything.’ ‘ As if I would! ’ (= surely you do not expect me to)
     “什么也别说。”“我才不会说呢！”

as it is

• 照现状
  considering the present situation; as things are
  1. We were hoping to finish it by next week─as it is, it may be the week after.
     我们本希望在下周完成——看样子可能要下下周才行。
  2. I can't help─I've got too much to do as it is (= already) .
     我帮不了忙——我已经有太多的工作了。

as it were

• 可以说；在一定程度上
  used when a speaker is giving his or her own impression of a situation or expressing sth in a particular way
  1. Teachers must put the brakes on, as it were, when they notice students looking puzzled.
     当老师发现学生神色茫然时，就应该在一定程度上放慢速度。

as to sth

as regards sth

• 关于；至于
  used when you are referring to sth
  1. As to tax, that will be deducted from your salary.
     至于税款，将从你薪水中扣除。

as you do

• （对刚说过话的评论）
  used as a comment on sth that you have just said
  1. He smiled and I smiled back. As you do.
     他微笑，我也报以微笑。真所谓礼尚往来。

as yet

• 直到现在；直至过去某时
  until now or until a particular time in the past
  1. an as yet unpublished report
     一篇尚未发表的报告
  2. As yet little was known of the causes of the disease.
     当时人们对这种疾病的起因几乎一无所知。

adv

1. to the same degree (often followed by `as')
   1. they were equally beautiful
   2. birds were singing and the child sang as sweetly
   3. sang as sweetly as a nightingale
   4. he is every bit as mean as she is

   Synonym:    equallyevery bit