定语从句：1)定语从句的定义在复合句中，修饰名词或代词的从句叫做定语从句。被定语从句所修饰的词叫先行词。引导定语从句的词叫关系词。关系词包括关系代词who(宾格whom,所有格whose),that,which和关系副词where,when,why等。Theboywhoiswearingablackcoatboughtadictionaryyesterday.Thenoodlesthat(which)mymothercookedweredelicious.TheschoolwhereIlearnedjudowasverylarge.Irememberthedaywhenourbandwasformed.Idon'tknowthereasonwhyshegotsoangrythismorning.2)定语从句的种类：定语从句可以分为限定性定语从句和非限定性定语从句。限定性定语从句：它是先行词在意义上不可缺少的定语，如果去掉，主句的意思就不完整或失去意义。这种从句与主句的关系十分密切，书写时不可用逗号分开。如果关系代词在限定性定语从句中作宾语，关系代词通常可以省略。Doyouknowthegirlwhojustcamein?Shanghaiisacity(that)I'vealwayswantedtovisit.Hersistermarriedaman(who/whom/that)shemetonaplane.ThetimewhenIfirstmetMr.Whitewasaverydifficultperiodofmylife.非限定性定语从句：它只是对先行词作附加补充说明，如果去掉，主句的意思仍然清楚完整。这种从句与主句的关系不是很密切，书写时往往用逗号分开。非限定性定语从句一般不用that引导，而且不可以省略关系词。Theoldwoman,wholivesonherown,hasacatforcompany.LoriisgoingtomarryMark,whomshedoesnotlove.Beijing,whichisthecapitalcityofChina,isaverybeautifulcity.关系代词的用法：在定语从句中，关系代词起着连接主句与从句，指代先行词和在从句中作句子成分的三重作用。关系代词的选用取决于主句中的先行词以及关系代词在从句中作何种成分。一.关系代词who,whom的用法(1)who可以代替人(即它的先行词必须是人)，在从句中担任主语，往往也可以代替在从句中担任宾格的whom，但它的前面不能有介词，如果带介词则必须用宾格whom,即"介词+whom".E.g.Jonnyisapersonwhoalwayshasnovelideas.ThegirlwhothefirstprizeinthecontestisfromZhejiang.Thepersonwho/whomyoujusttalkedtoisMr.Depp.---ThepersontowhomyoujusttalkedisMr.Depp.(介词to提到定语从句前，只能用whom.)We'llgotothehospitaltoseethepatients,mostofwhomarechildren.(whom前常用表示数量的词none/neither/both/each/allof…)⑵在定语从句中，who,that指人时可以通用，但在下列情况下用who,而不用that.A)先行词是one,ones,anyone时，宜用who.Onewhohasnothingtofearforoneselfdarestotellthetruth.Theoneswhoflattermedon'tpleaseme.Anyonewholaughslastlaughsbest.Anyonewhofailstofinishthetaskgivenshouldbecriticized.B)先行词为those时，宜用who.ThosewhowanttogototheGreatWallsignuphere.Nowordsarestrongenoughtoexpressourthankstothosewhoworkedhardtorescuesurvivorsintheearthquake.C)当先行词有较长的后置定语时，宜用who.ImetagirlinthestreetyesterdaywhogrewupinYunnanprovince.一个句子中带有两个定语从句时，其中一个定语从句的关系代词时that,另一个宜用who.E.g.Theboythatyoumetlastnightisthegroupleaderwhostudiesveryhard.D)在therebe开头的句子中，事宜用who.Thereisayoungmanwhowantstoseeyourfather.Therewasakingwhowaskindtohispeople.Therearemanyoldmenwhoareagainstthisplan.关系代词whose的用法：关系代词whose是关系代词who的所有格形式，它既可以代人，也可以代物。当whose代物时，相当于ofwhich.Whose引导的定语从句既可以是限定性定语从句，也可以是非限定性定语从句。DoyouknowPeterwhosefatherhappenstobeworkinginyourcompany?Thetouristwantedtobookaroomwhosewindowfacessouth.=Thetouristwantedtobookaroomthewindowofwhichfacessouth.=Thetouristwantedtobookaroom.Theroom'swindowfacessouth.WewenttoseeourteacherMissStyles,whosehusbandlosthislifeintheearthquake.Xi'an,whosewallsremainasgoodasbefore,isoneofthefewcitieswithcitywalls.二.关系代词that,which的用法(1)在限定性定语从句中指代...