aswhich引導定語從句的區(qū)別

1、which 與 as 引導的定語從句的區(qū)別眾所周知，which 與 as 都可以引導定語從句，但它們有許多用法上的區(qū)別，現就此簡要分析如下： 一、which與as引導非限制性定語從句的區(qū)別：1. . Which只能放在主句后面，而 as引導的從句位置相對較靈活，可在前，可在中，也可在后。例如：A) As he realized, I was very useful to him.( 在前 )B) Air, as we know, is a gas. (在中)C) He was a foreigner,as I know from his accent.( 在后 )2. 在 which 引導的定

2、語從句中，謂語動詞若是am, is, are 則這些系動詞不能省略；而as 后面若是這種情況，則可以省略。例如：A) He is a teacher, as (is) clear from his manner.(is 可以省略)B) He said he had never seen her before, which was not true.(was 不可省略)3. 當 which 引導的從句在意義上近乎并列關系時，可以用and this ， and that 代替，意思是“這件事”例如：A) He changed his mind, which(and this, and that)m

3、ade me very angry. 他改變了主意，這使我很生氣。B) She has married again, which(=and this, and that)was unexpected. 出乎意料的是，她又結婚了。而 as 主要起與上下文連接的作用，表達說話人的看法、觀點，并指出主句內容的出處或根據等，例如：C) Einstein, as we know, is a famous scientist. 愛因斯坦，眾所周知，是位偉大的科學家。D) As is announced in today s newspaper, we must improve our style of w

4、ork. 今天 的報紙上說，我們必須改進工作作風。4作主語時，which 既可以作系動詞be 的主語，也可以作實義動詞的主語；而這時as 只可以做系動詞be 的主語。例如：A) He married her, which was natural. (可用 as 代替 which )他和她結婚，這是很自 然的事。B) He won a/the Nobel Prize in chemistry, which made him illustrious. ( 不可用 as 代 替 which) 他獲得了諾貝爾化學獎，這使他名揚天下。5 .當定語從句位于主句之后，純粹表示主句所述內容，不帶有“如那樣”的

5、意思 時，往往用which,而不用as。例如：A) They were invited to the state banquet, which(as)was a great honor to them.他們被邀請參加國宴，這對他們來說是莫大的榮幸。B) We had to sleep in our wet clothes, which was most uncomfortable. 我們不得不 穿著濕衣服睡覺，這簡直太不舒服了。C) Mummy always treats me just like a baby, which I can t bear. 媽媽老把我當成 小孩對待，這讓我無法忍受

6、。6 .當定語從句有“如同那樣”含義時，用 as比用which更常見，而這些從句幾乎 成為固定說法。例如：A) Things will turn out contrary to one s wishes, as is often the case. 事與愿違，這 是常用的事。B) As was natural, this inordinate hope was followed by an excessive depression. 這 種過分希望之后，接著是極度的沮喪，是很自然的事。C) Chaucer is buried in “ poet s Corner ” ,as might hav

7、e been expected. 正如人們 已經預料的，喬叟被葬在“詩人角”。D) The material is elastic, as is shown in the figure. 這種霉爛有彈性，如圖所示。E) As we know( 眾所周知)F) As has been said above/before (正如前文所述)G) As has been pointed out (正如已經指出的)H) As might be imagined (可以想象得到)7當定語從句的關系代詞指的是先行詞本身時，只能用which 。例如：A) These apple trees, which I

8、planted three years ago, have not borne any fruit.這 些蘋果樹是我三年前種下的，沒結出任何果實。B) The Thames, which is now clean enough to swim in, was polluted for over a hundred years. 泰晤士河，現在已經干凈，可以在里面游泳，它曾被污染了一百多年。8.帶介詞的典型的定語從句，必須用 which ,不能用as。例如：A) There is a great deal of oxygen around us, without which we could n

9、ot live.我們周圍有許多氧氣，沒有它我們就無法生存。B) The shed in our garden, in which we often played, has lasted for a long time.我們經常玩耍的花園里的那個棚子，已經有很長時間了。二、引導限制定語從句時which與as的區(qū)別：1 先行詞如為表示物的名詞或代詞，在從句中又做介詞的賓語時，只能用which 。例如：This is the pan in which I boiled the milk. 這就是我煮牛奶的鍋。2 .前面有as時，引導定語從句的關系代詞用as,不用which。例如：There are

10、as many dictionaries as are needed. 所需要的字典都有了。3 .前面有such時，引導定語從句的關系代詞用as,不用which。1 ) Such women as know Tom thought he was charming. 認識湯姆的女人都認為他很 迷人。2 ) I have never heard such stories as he tells. 他講的那些故事我從沒有聽過。3 ) He is not such a man as I expected. 他不是我期望的那種人。1 .前面有the same時，引導定語從句的關系代詞用as而不用whic

11、h。例如：2 ) We are facing the same problems as we did years ago. 我們現面臨著和多年以前 同樣的困難。3 ) This is the same wallet as I lost. 這只錢夾子與我丟失的那只相同。4 ) I have the same trouble as you have. 我和你有著同樣的困難?？傊?， which 與 as 引導定語從句的區(qū)別要在實踐中多體會，體會多了，才能正確運用。補充：as, which 指代整個句子或短語。由 as, which 引導的非限定性定語從句，相當于and this 或 and that

12、 。在很多時候，表示說話人對話語的看法或態(tài)度，此時它們的先行詞并不是具體的某個詞，而是整個 句子或短語：The Chinese government has decided to develop the west of China, which, I dare say, will benefit the people there, especially those who are still leading a poor life. 中國政府決定開發(fā)西部，我敢說，這將造福于西部的人民，特別是那些至今過著貧窮生活的人。She has married again ， which delighted

13、 us. 她又結婚了，這使我們很高興。John said he d been working in the office for an hour ， which was true.The result of the experiment was very good ， which we hadn t expected.Carol said the work would be done by October ， which personally I doubt very much.2、 as, which 用在句末的時候，有些情況下可以互換使用。He was late for school ，

14、as/which was usual with him. 他上學遲到，這是家常便飯。He was a foreigner ， as/which I knew from his accent. 他是個外國人，我從他的 口音中得知這一點。I live a long way from work ， as/which you know. 我離上班的地方很遠，你是知 道這一點的。The author was brought up in a small village, as/which is recounted in some of his stories. 作者是在一個小村莊里長大的，這個問題在他的一

15、些小說了就被提到過。但是，當主句是否定句時，只能 as。例如：Spiders are not insects, as many people think. 蜘蛛不是昆蟲，而許多人卻認為蜘 蛛是昆蟲。3、 as 的特殊用法。1、如果要說明兩者有相似之處時通常用as,表達“正如（情形或事實所表示）的那樣、像的一樣”的意思。例如：She is a fine singer ， as her mother used to be. 她是一個很出色的歌唱家，和她 母親當年一樣。She is the same age as you (are).她和你年齡一樣大。 與 same.as 連用 I hope to

16、get such a dictionary as he is using. 我希望有一本和你正在用的一樣的詞典。 與 such.as 連用 us As water is to fish, so air is to man. 正如水對魚一樣重要，空氣對于人同樣重 要。She has married again ， as was/seemed natural. 她又結婚了，這很自然。2、as常與從句中的 know, see, hear, expect等動詞連用，也常用于 as often happens ， as is often the case（ 常有的事）等句子中。As you know, he is from Beijing. 正如你所知道的，他來自北京。As is known to everybody ， the moon travels round the earth once every month.He was absent ， as is often the case. 他沒有上學，這是常事。As you will find out, all is now settled. 你將會看到這樣的情況，一切都已搞定了。3、 as 引導的非限制性定語從句的位