语法专题二：名词性从句

语法专题二：名词性从句语法专题二：名词性从句1.名词性从句的基本概念：1)主语从句：在句中充当主语；亦可用it作形式主语，主语从句置于句末。2)宾语从句：在句中充当及物动词或介词的宾语；亦可用it作形式宾语，宾语从句置于句末。3)表语从句：在句中充当系动词的表语。4)同位语从句：常置于fact,idea,news,promise,doubt,suggestion,possibility,belief等表示有内容的名词后，起解释、说明作用。2.注意：1)名词性从句要用陈述句语序。2)名词性从句中缺少主语、表语、宾语时：常用what导，亦可用which表示选择，用who/whom/whoever指人。缺少状语：用where（表地点）,when（表时间）,how（表方式）,why（表原因）。3)如不缺成份：主语从句、同位语从句用that引导，不能省略；表从、单个动词宾从可省略引导词that；介词宾从、第二个宾从，引导词that一般不省略；it作形式主语或宾语时，引导实际主从或宾从，一般that不省略；当主从、宾从本身为复合句时，引导词that不省略。如：Hetoldussadlythatwhathehaddonesecretlywasdiscoveredbyhisparents.4)含宾从的复合句中，主句和从句的时态保持一致，但如果从句中表示是客观现象，虽然主句是过去时态，从句仍用一般现在时。5)主语从句做主语，谓语动词用单数；如果由and连接两个或两个以上的主语从句做主语时，谓语动词用复数；由两个或多个连接词引导一个主语从句，谓语动词用单数。6)当主句是I/Wethink（或suppose,expect,believe,imagine,guess）时，其后的宾语从句如果是否定的，常常把否定词not从从句中移到主句中。7)只能用whether，不能用if表示“是否”的情况如下：(1)在表语从句和同位语从句中；(2)在主语从句中，如果用it做形式主语，whether和if都能引导主语从句，否则，只能用whether(3)在介词之后；(4)后面直接跟动词不定式；(5)与ornot连用；(6)引导让步状语从句，只能用whether。8)同位语从句与定语从句的区别：同位语从句常放在表示具体含义的名词后，解释名词的含义或内容，该名词在从句中不充当成份；定语从句是对先行词限定和修饰，先行词在定语从句中充当成分。巩固练习：1.Weshouldthinkcarefullyabout______Mr.Needhamsaidatthemeeting.A.thatB.whatC.whichD./2.______youhaveseenthingslikethesebeforedoesn’tmatter.A.IfB.WhetherC.WhatD.When3.Shetookitforgranted______I’dbebackhomeanhourago.A.thatB.whetherC.ifD.when4.AtthattimeIhadnoidea______Icouldhandittohimwithoutbeingseen.A.ifB.howC.whichD.thathow5.LastSundayhepromised______today,buthehasn’tappearedyet.A.thathewouldcomeB.thathewillcomeC.hewillcometoseemeD.whetherhewouldcome6.Whatapity______is______youdidn’tarrivebydaylight.A.there;becauseB.it;thatC.he;whenD.that;for7.Fathermadeapromise______Ipassedtheexaminationhewouldbuymeanewdictionary.A.thatB.ifC.whetherD.thatif8.______isthemostusefulinvention?A.DoyouthinkwhichoftheseB.WhichofthesedoyouthinkC.WhichoftheseyouthinkD.Youthinkwhichofthese9.---Ibelieve______you’vedoneyourbestand______thingswillimprove.---Thankyou.A.that;/B./;/C.what;thatD./;that10.Itdependson______wehaveenoughtime.A.ifB.ifornotC.thatD.whether11.Youwillrealize______breaksthelawwillbepunished.A.thatthosewhoB.thatthosethatC.whoeverD.thosewhoever12.Idon’tdoubt______hewillcome.A.thatB.ifC.whatD.whether13.Whenandwhyhecamehere______yet.A.isnotknownB.arenotknownC.hasnotknownD.havenotbeenknown14.Thecityisnolonger______.A.whatitisB.thatitusedtobeC.whichitwasD.whatitusedtobe15.______wastheidea______thewifethoughtof?A.What;thatB.That;whatC.How;whyD.Why;how16.Oneofthemenheldtheview______thebooksaidwasright.A.whatthatB.thatwhatC.thatwhichD.whichthat17.______youdon’tlikehimisnoneofmybusiness.A.WhatB.WhoC.ThatD.Whether18.______hereallymeansis______hedisagreeswithus.A.What;thatB.That;whatC.Why;thatD.If;what19.---Don’tyoubelieveme?---______.I’llbelieve______yousay.A.No;whateverB.Yes;nomatterwhatC.Yes;whateverD.No;nomatterwhat20.LeiFengwasalwaysthinkingof______hecouldhelpothers.A.thatB.howC.whenD.which21.Canyoutellme______?A.whoisthatwomanB.whothewomanisC.whomisthewomanD.thatwomanis22.Outputisnowsixtimes______itwasbeforeliberation.A.thatB.whichC