课堂讲解用红色标注名词从句课堂讲解例句：主语从句：Thatthereisonlyonesolutiontothisquestionisclear.显然，这个方程只有一个解。ThatthisphenomenonhasconnectionwithreflectionmaybeseenfromFig.2.从图2中可以看出：这种现象与反射有关。3．Whichequationwewanttousewilldependonwhatdatawehavebeengiveninaproblem.我们使用哪个方程式将取决于在题目中给了那些数据。Howeachcircuitworksiscarefullyexplained.每个电路的工作原理在书中得到了仔细的解释。5.Whetherourunderstandingofradioactivitywillleadustouseitresponsiblyremainstobeseen.我们对于放射性的了解是否会使我们负责任地使用它，将拭目以待。主语从句的四种结构：一)It+连系动词+表语（形容词、名词、个别介词短语）+主语从句1.Itispossiblethattheyusethischemicaltotreatwater.他们可以用这种化学药品来净化水。2.Itseemsstrangethatthereshouldbetwodifferentkindsofinteraction.似乎很奇怪，竟然会存在两种不同的相互作用。3.Itisobviouswherethefaultlies.故障的所在位置是很明显的。4.Itisnowawell-knowfactthatallmatterismadeupofminuteparticles.5.常用句套子的译法应该熟记,如:Itisnecessarythat…必须……,有必要Itisessentialthat…Itisimportantthat…Itispossiblethat…Itislikelythat…Itisclear(evident,obviousapparent)that…二）It+be或get+过去分词+主语从句Itissaidthatmathematicsisthebaseofallothersciences.人们说，数学是其他各类科学的基础。Bysubstitutionitisfoundthatthissolutionsatisfiesthegivenconditions.通过代入，就可以发现这个解满足所给的条件。Itcannotbepredictedwhenthesemajorbreakthroughswillbeachieved.目前无法预言何时才能取得这些主要的突破。ItIsnotyetunderstoodwhichfactorsdeterminethesizeofthehigh-intensityfilaments.尚不了解哪些因素决定了高亮度灯丝的尺。Itisknownthat…我们知道Itiswellknownthat。。。众所周知，大家知道Itissaidthat据说Itisreportedthat据报道Itisbelievedthat据信Itcanbeseenthat可以看出Ithasbeenshownthat已经表明Itmustberememberedthat必须记住Itmustbepointedoutthat必须指出Itshouldbenotedthat应当注意Itwasfeltthatthebookshouldprimarilymeettheneedofcommunicationengineers.当时认为,本书应主要满足通讯工程师的需要。Itisassumedthestudenthasabasicunderstandingofmechanicaldrawing.作者认为学生应该对机械制图有基本的了解。Itistruewe’remadesomeprogressinremakingnature.诚然，我们在改造自然方面取得了一些进步。三）it+几个不及物动词（follow(得出)happen(有时，碰巧，发生)appear（似乎）matter（有关系）seem（似乎）turnout（结果，证明是））Fromaboveitfollowsthattheslopeatthatpointiszero.由此可以得出在该处的斜率为零。Itseemsthatthesetwobranchesofsciencearemutuallydependentandinteracting.似乎这两个科学分支是相互依存