as的用法.ppt

As的用法的用法As的四种词性的四种词性As有四种词性，即介词介词、副词、、副词、连词连词和和关系代词关系代词I. As作介词作介词1(1). 作 “如，像”解e.g① They got united as one man. ② She spoke of me as her closed friend.(2). 作“充当，作为”解e.g③ As a writer, he was famous. ④English is spoken as the first language be most people in Australia.(3). As作为介词，常和以下动词连用regard…as/be known as/consider…as use…as/ describe…as/be remembered as work as/ act as/be honored asWe regard the sun as the source of most forms of energy.2、、as单独使用单独使用 As可单独使用，意为“作为……,当作……”例如： The news apparently came as a complete surprise.这个消息显然让人大吃一惊。

I had natural ability as a footballer. 我天生就是当足球运动员的料3、、as做后置定语做后置定语 as用在名词后面，作后置定语，在意义上相当于所修饰的名词的同位语例如： Over the years, tools and technology themselves as a source of fundamental innovation have largely been ignored by historians and philosophers of science. 一直以来，工具和技术本身作为根本性创新的源泉，在很大程度上却被历史学家和科学思想家们忽视了II、、as作为副词作为副词 在as…as…结构中，前一个as是副词，后一个as是连词（有时可省略）；在否定句中，作副词的as可以用so代替例如： The book is pretty difficult. That one is as difficult. He is as tall as his father.III、、as作为连词作为连词 As做连词可引导时间状语从句（意为“随着…”）、原因状语从句（意为“既然，因为…”）、方式状语从句（意为“如，像”）、让步状语从句（意为“虽然，尽管”）和比较状语从句。

As the man grew older, he lost interest in everything except gardening. Young as he was, he made the greatest inventions this year. It’s not so easy as he said. 注意：as引导的比较状语从句中，如果主语是名词短语且较长，经常采用倒装结构（不用倒装也可以）例如：Reading is to the mind as is exercise to the body.IV、、as作为关系代词作为关系代词as作为关系代词，用来引导定语从句，包括限制性定语从句和非限制性定语从句1、、as引导限制性定语从句引导限制性定语从句 as引导限制性定语从句时，通常和such, the same, as（so）等连用，构成such…as/such as, the same as/ the same…as, as/so…as等结构，在从句中作主语、宾语和表语例如： Don’t trust such men as praise you to your face.（as作主语） You should read only such books as you can understand without much difficulty.（as作宾语）  注意注意：such…as与such…that, so…as与so…that的区别：that是连词，引出结果状语从句是连词，引出结果状语从句，在从句中不做成分；as是关系代词，引出定语从句是关系代词，引出定语从句，在从句中可作主语、宾语和表语。

比较： He is such a nice boy that everyone likes him. He is such a nice boy as everyone likes. 这个男孩的性格如此之好，人们都喜欢他 It is so difficult a problem that nobody can work it out. It is so difficult a problem as nobody can work out. 这个问题太难了，没有人能解决 2、、as引导非限制性定语从句引导非限制性定语从句 as引导非限制性定语从句时，通常指的不是主句中的某一个名词（先行词），而是指整个主句表达的内容，对主句所作的陈述进行附加说明，意为“这……,正如……”这种从句可位于主句之前、之中或之后例如： As we all know, Taiwan belongs to China. Taiwan, as we all know, belongs to China. Taiwan belongs to China , as we all know. 众所周知，台湾属于中国。

3、注意下面的习惯用法 as is well discussed正如已讨论过的 as is often said正如通常所说的 as is often the case通常就是这样 as has been pointed正如所指出的那样 as has been said before正如之前所说 as often happens如同经常所发生的那样 as might be expected正如所料 as is well known to all众所周知 4、在多数情况下，从句中的谓语动、在多数情况下，从句中的谓语动词可省略词可省略 as explained before如前面所解释的 as mentioned above如前面所提到的 as shown in the figure如图所示 as already discussed正如已讨论的 as seen from the table从表中可以看出ⅤⅤ. 含含as的固定词组的固定词组1.as soon as→引导时间状语从句 So/as far as I know→在句中作插入语。

意思是“据我所知”As/So far as I know, he will come here next Monday.2.As well as→并列连接词组，意思是：“和， 同”当其连接两个并列主语时，谓语动词应与前面的主语在数上保持一致也可以和短 语not only…but also进行替换My parents as well as my elder sister enjoy music. My elder sister as well as my parents enjoys music. Tom studies Japanese as well as Chinese.Tom studies not only Chinese but also Japanese. as well→译为“也，还”经常放在句尾与too, also同义词Come here early, and bring your brother as well. 4.So as to do sth./so…as to do sth.→引导 目地或结果状语He studies hard so as to pass the exam. He was so strong as to carry the heavy box. 5.such as→意为“例如，诸如”可用来引入同位语，举一例或数例说明它与之同位词的词 所含的具体内容。

There are different forms of energy, such as heat energy,light energy, sound energy and etc.6.as to(=as for/as regards)关于，至于 as much as/as many as “ 多达…，达到… 至多” There is no doubt as to his honesty. He can earn as much as 500 dollars a day.7.as a result/as a result of(由于……的结果) as a whole(就整体来说)/as follows(如下 ) as usual (照常)/as a (general) rule(通常) as a matter of fact(事实上)/as above(如上) as soon as possible/as early as possible as quickly as possibleMore examples:① She died as a result of the accident. ② The reasons are as above(as follows). ③ The machine runs as usual. ④ As a matter of fact, air is a gas. ⑤ His father gets up early as a rule. ⑥ You should improve your English as soon as possible.⑦When sound travels through air, the air, as a whole doesn’t move.⑧Today our life has been much better as compared with that before liberation. 和解放前比起来我们今天的生活好得多了。

练习 When a pencil is partly in a glass of water, it looks as if it（ B ）. A. breaks B. were broken C. has broken D. had been broken 本题为as if 引导的虚拟条件句，主句表示与常识相反，谓语动词应该使用过去时（ A）has already been pointed out , grammar is not a set of dead rules. A. As B. It C. That D. Which as引导定语从句，在定语从句中既充当成分又含有意义，意为“正如”。