as大学用法总结

As的用法小结as可以作连词、介词及关系代词和副词。

其用法如下:一、as作连词的用法:1.作“在……期间，当……的时候”引导时间状语从句.注意与when、 while的用法区别。

①下列情形时,只用as, 而不用when或while。1) 用于表示同一个人的两种动作交替进行,指一边……一边….如:The girl sings as she goes to school.He looked behind occasionally as he went forward in theforest.2)表示两个同步发生的动作或进行，意为随着…..的发展.如:As time went on / by, she became more and more beautiful.As children get older, they become more and moreinterested in everything.1/123)表示两个短暂行为或事情几乎同时发生.如:I watched her as she read the book.I thought of it just as you opened your mouth.Just as the flying worm hit her face, she gave a loudcry.4)接在名词后面表示某一个年龄段时.如:As a young man, he was active in sports.②when作"当……的时候"解,可以指较短的(一点)时间,也可指一段时间。如:When I was at college, I could speak several foreignlanguages. When the clock struck twelve, I had slept for 2hours.③ while常表示一段较长的时间或一个过程,强调主句谓语动词与从句谓语动词同时发生。如:Work while you work. Playwhile you play.

2. As =Since 作"既然"、"由于"解,引导原因状语从句,常用来表示已为人们所知或显而易见的原因或理由。如: As he’s been ill for ages, I will help him.2/12As / Since you're not feeling well, you may stay at home.As he wasn't ready , we went without him.

3. As =in the way that作"像"、"按照……的方式"解,引导方式状语从句。如:Do as I told you.Remember, you must do everything as I do.

4. 用于as… as或not / so/ as … as中,前一个as是副词,后一个as是连词,引导比较状语从句。如:They helped the old as much as possible.I don't speak English so/ as well as she does.

5. 表示虽然,尽管 等,引导让步状语从句,常用倒装语序, 如果表语有冠词a/an, 需去掉模式为:adj. /adv. / n.+ as +主语+谓语+主句。如: Young as he is, he knows much.Tired as they were, they walked on.3/12Great scholar as he is, he is lacking in common sense.

6. 固定句型：“主句，as +be/do+主语”表示也…一样。如: She is a doctor, as was her husband.二、as作关系代词,引导定语从句,表示正如、这一点…如:He is very careful, as we all know.As is well-known, Taiwanbelongs to China.另外当先行词被the same, such等词修饰时,常用as来引导定语从句。如:Such a clever girl as she can learn anything quickly.I was reading the same book as he bought yesterday.三、as作介词的用法.1.表示好像。如:He dressed as a policeman.

2. 表示作为当作。如：I found a job as a guide.4/12

3. 当某人是某身份时。如：As a child , she was sent to abroad.

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:As a Party member, I'll take the lead in everything. (状语)She works as a model. (状语)She has me as one of her best friends.(引起宾语补足语)

5. 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”。

四、作副词的用法1. 表示与…等同。如：This dress is twice as expensive as that one.

2. 像，如等。

5/12如：As before, he remained unmoved.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 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6/12 关系代词作定语从句主语时的省略关系代词在定语从句中除作宾语可以省略外，在下列情况下，作主语也可以省略。1．定语从句中含there be，作定语从句主语的关系代词可以省略。如：You must make a list of the names of the students thereare in your class．你必须列一张你班同学的名单。He showed me thedifference there is between what is right and what is wrong．他给我指出了对和错的不同之处。

2．主句以there be开始，作定语从句主语的关系代词可以省略。如：There is something keeps worrying me．有些事一直使我担心。There is a teacherhere can speak Spanish．这里有一位老师能说西班牙语。

7/123．主句以that is／was开始的句子中，作定语从句主语的关系代词可以省略。如：That's all is today's homework．今天的家庭作业就是这些。（all后省去that）Was that someoneposted your letter？是有人帮你把信寄走了吗？（someone后省去that）4．主句以here is，here are开始，作定语从句主语的关系代词可以省略。如：Here is theprofessor comes from the Oxford University．这是从牛津大学来的一位教授。（professor后省去who）Here are three orfour of us got a full mark in the examination．我们这里三四个人考试得了满分。（us后省去who）8/125．主语以have（意思是“有”）作谓语，作定语从句主语的关系代词可以省略。如：I have two morepeople should come to help me．我还有两个人应该来帮助我。（people后省去who）We have words tospeak to those people will be put to do the work．我还有话要对派去做这工作的人说。（people后省去who）