Module3Unit2GrammarandusageLearninggoalslearnthatthepreparatorysubject/emptysubjectitisoftenusedtobalancethesentencewithalongsubject.Theemptysubjectitactsasitsgrammaticalsubjectandtherealsubjectisattheendofthesentence.ThatweshouldimproveouroralEnglishisimportant.ItisimportantthatweshouldimproveouroralEnglish.preferablecorrectWhichoneisbetterPreparatorysubject"it"Readthenotesonpage30.Preparatorysubjectit

形式主語it通常情況下，當(dāng)句子的主語很長（是從句,動詞不定式或動名詞短語時），我們一般用it作形式主語，讓句子結(jié)構(gòu)更加平衡，避免頭重腳輕。形式主語it在語法上起到主語的作用，而句子的真正的主語則在句尾。

whenweuseanounclauseasthesubjectofasentence.當(dāng)句子的主語是從句時，我們一般用it作形式主語。a.(correct)Thatlanguagesborrowwordsastheyaredevelopingisinevitable.=(preferable)Itisinevitablethatlanguagesborrowwordsastheyaredeveloping.b.(correct)Whether“borrowedwords”aregoodorbadremainsaquestion.=(preferable)Itremainsaquestionwhether“borrowedwords”aregoodorbad.1.Wecanuseitasanpreparatorysubject.Preparatorysubject“it”:1.ThatwewouldbenotabletounderstandOldEnglishtodayiscertain.=ItiscertainthatwewouldnotbeabletounderstandOldEnglishtoday.2.WhetherEnglishwillcontinuechanginginthefutureiseasytoanswer.=ItiseasytoanswerwhetherEnglishwillcontinuechanginginthefuture.3.Whenwecansetoffdependsontheweather.=Itdependsontheweatherwhencanwesetoff.(correct)Tomasteraforeignlanguageishard.(preferable)Itishardtomasteraforeignlanguage.b.(correct)TogainaccesstotheInternetisimportantforus.(preferable)ItisimportantforustogainaccesstotheInternet.B.whenthesubjectisato-infinitive.當(dāng)句子的主語是不定式時，我們一般用it作形式主語。C.whenthesubjectisav-ingform.當(dāng)句子的主語是動名詞v-ing時，我們一般用it作形式主語。a.(correct)Itisdifficulttostopsmoking.=(preferable)Smokingisdifficulttostop.b.(correct)IttakesalotofmytimetravellingtoBeijing.=(preferable)TravellingtoBeijingtakesupalotofmytime.Weusuallyusethepreparatorysubjectit

withaclauseorto-infinitive(preferable),butwiththev-ingformweprefertherealsubjectatthebeginning.

通常情況下，當(dāng)句子的主語是從句或動詞不定式時，我們一般用it作形式主語。當(dāng)句子主語是動詞的-ing形式時，我們則一般將真正的主語置于句首，而不使用it作形式主語。Tip2.當(dāng)seem,appear,happen,turnout和prove在句子中作謂語動詞時，我們也可以使用形式主語it。Itseemsthathespeakstwolanguages.=Heseemstospeaktwolanguages.b.Mynewneighborhappenstocomefrommyhometown.=Ithappensthatmynewneighbor

comesfrommyhometown.3.在Itisknown...;Itissaid...;Itishoped...;Itisbelieved...等句型中。如:

Itissaidthatourschoolfootballteamwon.·

主語從句也可以用it作形式主語,以wh-連接的句子作真實(shí)主語,放到句子后面.如:

Itisstillaquestionwhenweshallhaveoursportsmeet.

Itdoesn'tmatterwhatyousay.4.Itis/was+被強(qiáng)調(diào)部分+that/who...

該句型是強(qiáng)調(diào)句型。被強(qiáng)調(diào)部分可以是主語、賓語、表語或狀語。強(qiáng)調(diào)的主語如果是人，that可以由who換用。如果把這種句型結(jié)構(gòu)劃掉后，應(yīng)該是一個完整無缺的句子。這也是判斷強(qiáng)調(diào)句型與其它從句的方法。

ItisonTuesdaythatshewillcome.FinishexercisesA&B,page31ThekeytoExerciseA(2)Itrequiresagoodunderstandingoftheirbehaviortoknowwhattheymean.(3)Italwayspuzzlesmewhymydogbarksincertainways.(4)Itwon’tbedifficulttobuyamachinelikethis.ThekeytoExerciseB2.IthappensthatseveralracialgroupsliveinSingapore.3.Itisfuntoheardifferentpeoplespeakingdifferentlanguagesallatthesametime.4.ItiscertainthatI’llseeyounextweek.高考鏈接1.Itwasneverclear_______themanhadn’treportedtheaccidentsooner.(2011江蘇)A.thatB.how C.when D.whyD2.I’mafraidhe’smoreofatalkerthanadoer,whichis______heneverfinishesanything.(2011山東)A.thatB.whenC.whereD.whyD3.Beforeaproblemcanbesolved,itmustbeobvious_______theproblemitselfis.(2011湖南)A.whatB.thatC.whichD.whyA4.（2012上海卷）—We'veonlygotthissmallbookcase.Willthatdo—No,______Iamlookingforissomethingmuchbiggerandstronger.whoB.thatC.whatD.whichC5.（2012全國卷）Itisbynomeansclear____thepresidentcandotoendthestrike.A.howB.whichC.thatD.whatD6.(2013湖南)Donotletanyfailuresdiscourageyou,foryoucannevertell_______closeyoumaybetovictory.A.howB.that