Unit2HealthyLifestyleDiscoverUsefulStructures课件高中英语人教版选择性

LearningAboutLanguageDiscoverusefulstructuresLeadingin1.Differentformsofinfinitive.类别主动语态被动语态意义一般式todo完成式进行式/完成进行式/tobedonetohavedonetobedoingtohavebeendoingtohavebeendone发生在谓语动词之后发生在谓语动词之前正在进行一直持续1.Tochangebadhabits

isnevereasy.2.Ittookthesurgeonthreehourstofinishmymother’slungsurgery.3.TojointhePeople’sLiberationArmy,itisrequiredformentoshaveofftheirbeards.4.

Itwasnotpolitetodisturbyourneighborswithloudmusiclastnight.2.Payattentiontotheitalicizedinfinitivesanddiscussthemeaningsandfunctionsoftheitalicisedinfinitives.【总结】1.1-4句子中动词不定式都是作___语。2.句3和句4中it作__________，真正主语是后面的_______。主

形式主语todoTobeworkingalldaylongisabore.整天干活使人厌倦。(不定式进行式)Tohaveknownyouisaprivilege.认识了你真是荣幸。(不定式完成式)Togetupearlyisnecessary.早起是必要的。1.不定式作主语通常位于句首，表示具体的某次动作，谓语动词常用单数。Analysing:infinitiveusedassubject单个不定式作主语，谓语动词用_______两个或两个以上的不定式作主语，若语意一致或作为一个整体，谓语动词用_______两个或两个以上的不定式作主语，若语意不一致，谓语动词用________单数单数复数2.动词不定式与疑问词who,whom,whose,what,which,when,where,how连用构成不定式短语做主语。不定式作主语，有时根据表达的需要，可以在添加疑问代词或副词疑问代词：who，whom，what，which疑问副词：when，where，howwhether疑问词+todo可作主语,相当于一个主语从句。疑问词包括疑问副词when、where和how及疑问代词who(m)、what、which、whose。连接词whether也适用。3.当主语较长，谓语较短时，常用it作形式主语放在句首，而将真正的主语—不定式放到谓语的后面。It’snoteasytoworkouttheproblem.=Toworkouttheproblemisnoteasy.计算出这道题不容易。Itisinterestingtoplaywithsnowinwinter.冬季里玩雪是很有趣的。Itisterribletoseetheshipsinkingintothesea.目睹轮船沉入大海，真是太可怕了。为保持句子平衡，用it来作形式主语,相关句型有：（1）Itis/was＋形容词＋(for/ofsb)＋动词不定式若形容词描述事或行为的特征,用for,如difficult,possible,necessary等

若形容词描述人的品格、特点,用of,如kind,polite,impolite,rude,foolish等（2）Itis＋a/an＋名词(如apity/anhonour...)＋todo...（3）Ittakes/costs/requires...sb/sthtodosth

做某事花费某人多长时间/钱（4）Itis

useless/nouse/nogood/awasteoftime

doingsth（5）Itis

fun/nofun

doingsth

4.动词不定式与动名词作主语时的区别：（1）表示一般的、泛指的或习惯性的行为用动名词；表示具体的、一次性的或将来的动作用不定式。Swimmingisfuninsummer.夏天游泳是有趣的事。Toswiminthisriverisagreatpleasure.在这条河里游泳是件非常快乐的事。注意：有时这种区别并不很严格。但要注意：主语和表语要用同一种形式；平行结构中要用同一种形式。Toseeistobelieve.＝Seeingisbelieving.眼见为实。（2）

动名词作主语并不是表示某动作正在进行，而是表示经常性或习惯性的行为；不定式的进行时作主语才表示具体的某一动作正在进行。比较：It’snicehavingfriendstochatto.有朋友聊聊天是很惬意的。(经常性、一般性或习惯性的行为)It’snicetobetalkingwithyouhere.在这里跟你交谈是非常愉快的。(一次具体的正在进行的行为)5.不定式短语作独立成分

tobegin/startwith首先

tosumup总而言之

toconclude总而言之

totellthetruth说实话

tobefrank坦白地说

tobehonest说老实话tobebrief简言之

一些不定式短语可用作独立成分，通常位于句首，有时位于句中或句末，要用逗号同其他句子成分隔开。1.Jointhewordstomakefullsentences.1.important/avoid

/passivecigarettesmokingItisimportanttoavoidpassivecigarettesmoking.2.willtake/nutritionspecialist/abalanceddietmenu/make/anhour/

foryou____________________________________________________________3.useful/turnto/fitnessconsultant/foradvice____________________________________________________________4.illegal/dangerous/take/drugs____________________________________________________________5.harmful/skipbreakfast/often____________________________________________________________Itwilltakenutritionspecialistanhourtomakeabalanceddietmenuforyou.Itisusefultoturntofitnessconsultantforadvice.Itisillegalanddangeroustotakedrugs.Itisharmfultoskipbreakfast(too)often.Practice2.Jointhesentencestomakeaparagraph.Youcanaddyourownsentencesifnecessarytomakeyourparagraphmoremeaningful.3.Completetheconversationswiththecorrectformsofthephrasesinthebox.1.A:Hello,doctor.Iwanttoloseweight,butIjustcan’tseemtodoit.Whatcanyou

dotohelpme?

B:Well,first,it’snecessaryto_____________whatyoueat.Cutoutallfattyfoodand

sugarydrinks,andeatmorefruitandvegetables.2.A:

Ireallyneedto

________awaytoexercisemore.Icoulduseafitnessapp,but

myphone’sfull.

B:

Sodeleteafewfiles.I'msuretheappdoesn'ttakeupmuchspace.3.A:Beforeexercising,alwaysdoafewwarm-upsto___________.

B:

Iknow.ButthenIalwaysfeeltootiredtocontinue!4.A:ShouldIgoforthepizzaorthefriedchicken?Ihate_____________likethese.

Youknowwhat—I'mgoingtoeatboth!

B:Wow!Don’teattoomuchjunkfood—you’llgetfat.I’veactually_______________

togoonadiet,so

I’lljuststicktothefruitsalad.decideonbeginwithbeincontrolofmakeachoicedecideonmakeupone’smindbeincontrolofmakingachoicemadeupmymindbeginwithYoudon’tneedtobetoldthatitisdifficult1.______(lose)weight.Or,2._______(keep)theweightoffonceyouhavedroppedthosepounds.Now,itistimeforyou3.___________(identify)thefactorsthatcauseyouroverweight.Forinstance,youmaydiscoverthatyouspendtoomuchtime4._________(be)inactive.Or,thatyoutendtoskipmealsandsnackinstead.Onceyou5._____________(figure)outtheproblem,youwillfindyourselfonestepclosertocorrectingyourissues.6.________(eat)healthyfoods,gettingenoughsleep,andexerc