which与as引导非限制性定语从句的异同.doc

which与as引导非限制性定语从句的异同which与as一样，都可以引导非限制性定语从句，它们既有相同之处，也有差别。因此在实际运用中容易混淆。它们的某些用法在高考中也会考查。一相同点。两者引导非限制性定语从句时，可指代主句中的部分或整个句子的内容，在从句中做主语，宾语或表语，位于主句之后有时可互换。The meeting was put off, as /which was exactly what we wanted.He was a doctor, as/which I knew from his manner.二 不同点1. as可指其前后主句提到的事实或情况，因此引导的非限制性从句位置比较灵活，which可以放在主句前后，也可插入主句之中；而which引导的非限制性从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.在非限制性从句中，which后的be动词不可省；as而后的be动词可以省略。She told me she won the match , which was a lie.The material is elastic, as (was) shown in the figure.3. which在非限制性定语从句做主语时可用各类动词做谓语；而在非限制性定语从句做主语时，谓语常用连系动词，如be, seem, become等，一般不用其他行为动词。He saw the girl, which delighted him.He didnt say anything at the meeting , as/which seemed very strange.4. 如果主句中叙述的事情与从句所涉及的意向一致，多用as，用以对主句的意义进行补充；如果不一致，就用which She has married again, as was expected.He broke the rules again, which was unexpected.5.如表示“如同。那样，按照，正如”含义，常用as，这里as主要起与上下文联系的作用，表达说话人的看法，并指出内容，出处和根据等，常用的结构有as we know（众所周知）as often happens（正如常发生的那样）as is often the case（情况常常如此）as we all can see（正如我们看到的）be+announced/expected/known/imagined/mentioned/said/shown/reported（正如所。）等。这些结构常放句首，偶尔也可以放句中或句末As is known to all, China is a developing country.Kate was late for school , as often happened.6.在非限制性定语从句中关系代词指代主句中某一个单词时，常用which My brother enjoyed playing basketball , which he really plays well.Beijing , which he was born in, is our capital.7.在非限制性定语从句中“介词+关系代词（介宾代物）”中关系代词只能用which The Travel Agency, with which our company has been dealing for several years, has opened for new branchesAir is a mixture of gases, of which oxgen forms 21 percent.8.有时用case, point, time, situation或reason等抽象名词来总结主句的内容，可用“介词+ which +抽象名词”构成从句Ten years of hard work changed her greatly , for which reason he could hardly recognise her at first sight.The machine may be out of order , in which case it will be repaired at once.9.在非限制性定语从句关系代词用以代表主句中谓语的整个概念，从句中的谓语动词是否定形式时，常用which He can write a letter in English, which I can not.Metal will bear beating with a hammer, which a stone willl not 10.在非限制性定语从句关系代词代表前面主句中的宾语从句时，常用which He said he had passed the exam , 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.who B.that C.as D.which2.Jim passed the driving test,_surprised everybody in the office.A.which B.that C.this D.it3.The road conditions there turned out be very good,_was more than we could expect.A.it B.what C.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 time B.for which time .during whose time D.by that time 5.The Science Museum ,_we 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.what B.that C.how D.as7._I expained on the phone , your request will be considered at the next meeting.A.When B.After C.Wha tD.Since8._is often the case, we have worked out the production plan.A.Which B.When C.What D.As9. _has been announced , we shall have our f