NounClauseI.Formation1.连接词that/whether/ifWhetherhewillcomeornotisunknowntous.Mysuggestionisthatyoushouldthinkitoverbeforecomingtoadecision.Idon’tknowifyouwilljoinusinthesingingcontest.Thefactthathesucceededintheexperimentpleasedeverybody.Note:whether/ifArethefollowingsentencescorrect?(1)Itisaquestionofifweshouldgo.介词后的宾语从句只能用whether，不能用if(2)ThequestionifthePrimeMinistershouldresignmustbedecidedsoon.引导同位语从句通常用whether，不用if(3)HisfirstquestionwaswhetherTomhadarrivedyet.引导表语从句通常用whether，不用if(4)Ifshecomesornotmakesnodifference.If引导的主语从句只能放句后。（5）Idon'tknowwhetherornottheywillcomeforourhelp.（6）Idon'tknowifornottheywillcomeforourhelp.（7）Idon'tknowiftheywillcomeforourhelpornot.当whether与ornot连成一个词组时，whether不可换用if。若whether和ornot不连在一起，在口语中可以用if取代whether。Iamnotcertainif/whetherthetrainwillarriveontime.Idon'tcareifyourcarbreaksdownornot.Idon'tcareifornotyourcarbreaksdown.(8)Hedoesn'tknowwhethertostayornot.(9)Shedoesn'tknowiftogetmarriednoworwait.在动词不定式之前，只能用whether，不能用if。（10）Wediscussedifweshouldmakeachangeinourplan.（11）Wewerediscussingwhetherweshoulddiscussthebusinesswiththem.在及物运动discuss后的宾语从句中，只能用whether，不能用if。doubt/doubtful引导的宾语从句中，若主句是肯定句，从句连接词用whether/if;若主句是否定句或疑问句，从句连接词用that.P213Idoubtwhetherhewillbeelectedaschairman.Idon’tdoubtthathewillpasstheexam.但当doubt做“不信”解时，在肯定句中可接that从句。区别：Idoubtthatit’strue.Idoubtwhetherit’strue.2.关系代词：who/whom/whose/what/whichwhoever/whomever/whatever/whicheverWhathadyoudonetohimturnedhimagainstyou.Whateverthatisworthdoingshouldbedonewell.ThepictureremindedmeofwhatthatIhadseennearalake.关系代词既起连词作用，又充当从句中的主语、宾语、定语、表语等成分。其后不能再加连词。Note：who/whomever/whoeverHewillgivethebookto_________helikes.Hefeelssurethat_________winstheelectionwillhavethesupportofbothparties.作不带先行词的关系代词时，只能用whoever/whomever，不能用who。whoever=anyonewho，它本身兼有先行词和关系代词。而who只是关系代词，用它则缺少先行词。what/whose/which+n.Idon’tknowwhichclassmatesentthemoneytomyparents.Iwonderwhatideasuddenlyoccurredtoher.Theyaskedmewhosefathertheteacherwastalk