1、which與as引導非限制性定語從句的異同which與as一樣,都可以引導非限制性定語從句,它們既有相同之處,也有差別。因此在實際運用中容易混淆。它們的某些用法在高考中也會考查。一.相同點。兩者引導非限制性定語從句時,可指代主句中的部分或整個句子的內容,在從句中做主語,賓語或表語,位于主句之后有時可互換。The meeting was put off, as /which was exactly what we wanted.He was a doctor, as/which I knew from his manner.二.不同點1. as可指其前后主句提到的事實或情況,因此引導的非限制性從

2、句位置比較靈活,which可以放在主句前后,也可插入主句之中;而which 引導的非限制性從句只能位于主句之后。As is known to all, fish cant live without water.Air, as we know, is gas.2.在非限制性從句中,which后的be動詞不可省;as而后的be動詞可以省略。She told me she won the match , which was a lie.The material is elastic, as (was shown in the figure.3. which在非限制性定語從句做主語時可用各類動詞做謂語

3、;而在非限制性定語從句做主語時,謂語常用連系動詞,如be, seem, become 等,一般不用其他行為動詞。He saw the girl, which delighted him.He didnt say anything at the meeting , as/which seemed very strange. 4. 如果主句中敘述的事情與從句所涉及的意向一致,多用as,用以對主句的意義進行補充;如果不一致,就用whichShe has married again, as was expected.He broke the rules again, which was unexpec

4、ted.5.如表示“如同。那樣,按照,正如”含義,常用as,這里as主要起與上下文聯系的作用,表達說話人的看法,并指出內容,出處和根據等,常用的結構有as we know(眾所周知as often happens(正如常發生的那樣as is often the case(情況常常如此as we all can see (正如我們看到的 be+announced/expected/known/imagined/mentioned/said/shown/reported (正如所。等。這些結構常放句首,偶爾也可以放句中或句末As is known to all, China is a develo

5、ping country.Kate was late for school , as often happened.6.在非限制性定語從句中關系代詞指代主句中某一個單詞時,常用whichMy brother enjoyed playing basketball , which he really plays well. Beijing , which he was born in, is our capital.7.在非限制性定語從句中“介詞+關系代詞(介賓代物”中關系代詞只能用whichThe Travel Agency, with which our company has been de

6、aling for severalyears, has opened for new branchesAir is a mixture of gases, of which oxgen forms 21 percent.8.有時用case, point, time, situation或reason等抽象名詞來總結主句的內容,可用“介詞+ which +抽象名詞”構成從句Ten years of hard work changed her greatly , for which reason he could hardly recognise her at first sight.The ma

7、chine may be out of order , in which case it will be repaired at once.9.在非限制性定語從句關系代詞用以代表主句中謂語的整個概念,從句中的謂語動詞是否定形式時,常用whichHe can write a letter in English, which I can not.Metal will bear beating with a hammer, which a stone willl not10.在非限制性定語從句關系代詞代表前面主句中的賓語從句時,常用whichHe said he had passed the exa

8、m , which was untrue.1.The owner of the cinema needed to make a lot of improvements and employ more people to keep it running ,_meant spending tens of thousands of pounds.A.whoB.thatC.asD.which2.Jim passed the driving test,_surprised everybody in the office.A.whichB.thatC.thisD.it3.The road conditio

9、ns there turned out be very good,_was more thanwe could expect.A.itB.whatC.which .that4.Mark was a student at this university from 1999 to 2003,_he studied very hard was made Chairman of the Students Union.A.during which timeB.for which time .during whose time D.by that time5.The Science Museum ,_we

10、 visited during a recent trip to Britain , is one of Londons tourist attractions. A.which B.what C.tha tD.where6.The Beatles,_many of you are old enough to remember, came from Liverpool.A.whatB.thatC.howD.as7._I expained on the phone , your request will be considered at the next meeting.A.WhenB.AfterC.Wha tD.Since8._is often the case, we have worked out the production plan.A.WhichB.WhenC.WhatD.As9. _has been announced , we shall have