Grammar名词性从句包含：宾语从句：介宾结构；动宾结构表语从句：系表结构(系动词后面跟一个从句)主语从句:一个句子做主语同位语从句：对名词进行解释说明判断以下从句：1.Chinaisnolongerwhatsheusedtobe.2.Thequestionremainswhethertheywillbeabletohelpus.3.ItseemedasifIcouldn'tthinkoftherightword.4.ThereasonwhyIstudyhardisthatIwanttogotoakeyuniversity.5.Theybelieveinthatshemuststillbesingle.6.IknownothingabouthimexceptthatheislivinginBeijing7.Idon’tknowwhetherhe’sfreeornot.8.MaryaskedwhetherIwasdoingmyhomeworkornot.9.I’mthinkingofwhetherweshouldgofishing.10.Weareworriedaboutwhetheritwillraintomorrow.(1).连接词：that在句子中不充当任何成份，无意义，不可省略Thathewillwiniscertain.Thathegotthefirstprizemadehisparentsveryhappy.ThatChinahasbecomestrongiscertain.Thattheyloveeachotherisobvious.Thatheplayedcomputergamesintonightmadehisparentsdisappointed.(2).连接词whether在句中不充当成份，意为“是否”Whetherwegobytrainorbyboatmakesnodifference.Whetherlifeexistsonotherplanetsisnotclear.Whetherhe’llcomehereisn’tclear.Whethertheoldbusstationshouldbereplacedwithamodernhotelornotisunderdiscussion.(3).连接副词when(时间),where(哪里),why(为何),how(怎么；怎样)有词义，在从句中担任状语。WhyChenLincommittedsuicidehasnotbeenclearyet.Howthishappenedisnotcleartoanyone.Wherehefoundthetreasureremainsamystery.Whenwewillholdthegraduationceremonyhasnotbeendecidedyet.Whentheywillleaveisnotdecided.(4).连接代词：who(谁，主格);whom(谁；宾格);whose(谁);what(什么…事/话…);which(哪一个);whoever(不论谁),whatever(不论什么),whichever(不论哪一个)在句子中担任主语，宾语，表语或定语主语从句能用it做形式上主语(二)注意:由that引导主语从句有时为了使句子结构平衡,防止“头重脚轻”,惯用it作形式主语,而把从句放在后面。比如:这么就组成了下面一些惯用句型:1)Itis+n.+从句Itisapity/shamethat...遗憾是……Itisasurprisethat…令人惊奇是…Itisafactthat……是事实Itiscommonknowledgethat……是常识*_______________(很遗憾)welostthematch.*______________(这是事实)hecheatedintheexam.2)Itis+adj.+从句It’scertainthat…必定…Itispossiblethat...很可能……Itisunlikelythat...不可能……Itisobviousthat…很显著…Itisnecessary\important\natural\...that…*_________________(很可能)shewillcomebacktomorrow.*_________________(很显著)thismeasureiseffective.3)It+be+过去分词+从句Itissaidthat...听说……Itisknowntoallthat...众所周知……Itisreportedthat