Unit2HealthylifestyleDiscoveringUsefulStructuresP17課件高中英語人教版選擇性

新人教選擇性必修Book3Unit2HealthyLifestyleDiscoverusefulstructuresP17infinitiveassubject不定式作主語toenablethestudentstomastertheusageoftheinfinitiveoftheverbasthesubjecttoenablethestudentstousetherelevantgrammarflexiblyandauthenticallyintherealsituationLearningObjectivesUnderlinethesentencesinthetextandanalsysethefunction.However,duringthisperiod,itcanbeeasyforsomeofthemtoformbadhabits.主語Topreventharmfulhabitslikethesefromdominatingateenager’slifeisessential.主語Theymustlearntorecognisebadhabitsearlyandmakeappropriatechanges.賓語Tochangebadhabitsisnevereasy,evenwithmanyattempts.主語Wemakeachoicetodosomething,andthenwerepeatitoverandoveragain.定語Lead-inFindmoreintherestofthetext.Presentation/PracticeMymumkeepstellingmetogooutwithmyschoolfriendsinstead.It’simportanttomeetfriendsinpersonfromtimetotime,notjustonsocialmedia.WhenIsetouttodosomething,Idomybesttoachieveit.Mytargetistopreparemyselfformydegreeinbiologyatuniversity.LiYingisthefirstpersontojointhevolunteeringclubinherclass.complement賓語補足語subject主語adverbial狀語predicative表語attribute定語Listthefunctionsoftheinfinitivesinthesentences.動詞不定式

動詞不定式作主語

不定式作主語，表示具體的、一次性的或?qū)淼膭幼鳎辉诤芏嗲闆r下，人們通常用it作為形式上的主語，而把不定式移到謂語之后，使句子結(jié)構(gòu)顯得平穩(wěn)一些。Toseeistobelieve.眼見為實（Seeingisbelieving)Itisessentialtogiveupsmoking.It’sveryniceofyoutohelpme.1.不定式具有名詞的特征，可在句子中充當(dāng)主語。

Toknowoneselfisdifficult.

人貴有自知之明。

動詞不定式作主語

不定式和動名詞作主語的區(qū)別不定式：表示具體的某次動作，一次性的，將來的動作。

Toteachyoutheusesoftheinfinitiveismytasktoday.

教你們不定式的用法是我今天的任務(wù)。動詞-ing形式：表示比較抽象的、經(jīng)常性的、一般性動作。

Teachingismyjob.

教學(xué)是我的工作。2.不定式和when/where/how/what/whether等連用，在句子中

作主語。Whethertodoit

hasn’tbeendecided.是否去做還沒有決定。Itis+形容詞+forsb.+todosth.常用于表示事物的特征特點，表示客觀形式的形容詞，如easy,hard,difficult,interesting,impossible等。Itis+形容詞+ofsb.+todosth.的句型一般用表示人物的性格、品質(zhì)，表示主觀感情或態(tài)度的形容詞，如good,kind,nice,clever,foolish,right等。3.it作形式主語句型：It’sverysillyofyoutofoolme.It’sverysillyforyoutodosuchthing.4.Itis+a/an+名詞+todosth.這樣的名詞有：apity,ashame,apleasure,one’sduty,anhonor等。It’sagreathonortobeinvitedtoyourbirthdayparty.很榮幸被邀請參加你的生日聚會。

動詞不定式作主語

5.Ittakes/costs/requires/makessb./sth.todosth.Ittookmetwohourstofinishthework.我完成那項工作用了兩小時。注意：在Itis+nouse/nogood/useless/fun/enjoyable/tiring/interesting/foolish/nice/awasteoftime/apleasure...句型中常用動名詞形式做真正的主語。It’snousewaitingheredoingnothing.It’snouseforustowaitheredoingnothing.

（1）Sometimesit’sbetter

___(remain)silent.（2）Although

isahardtasktoprotectourenvironment,wecan’thelpbutgoahead.

（3）

______

(control)theairpollutionisnecessary.（4）Itwasfoolish

himtoendangerhislifeinthatway.（5）Don’tyouthinkitisrude

himtoaskaladyherage?Practice語法填空：根據(jù)提示完成句子。ofofitTocontrol/Controllingtoremain（6）Itisdifficult

himtoliveonsuchasmallsalary.（7）Idon’tthink_________________________（你問……是不

禮貌的）howlongtheinterviewwilllast.（8）

_____

（保衛(wèi)……是我們的職責(zé)）thecountryagainstitsenemies.（9）

___

（……花了我半個小時）towashtheclothes.Practice語法填空：根據(jù)提示完成句子。foritisimpoliteofyoutoaskIt’sourdutytodefendIttookmehalfanhour ProductionJointhewordstomakefullsentencesusingtheinfinitive.1.important/avoid/passivecigarettesmoking._________________________________________________2.willtake/nutritionspecialist/abalanceddietmenu/make/anhour/foryou.____________________________________________________________________________________________________2Itisimportanttoavoidpassivecigarettesmoking.Itwilltakeanhourforanutritionspecialisttomakeabalanceddietmenuforyou.ProductionJointhewordstomakefullsentencesusingtheinfinitive.3.useful/turnto/fitnessconsultant/foradvice__________________________________________________4.illegal/dangerous/take/drugs__________________________________________________5.harmful/skipbreakfast/often_____________________________________________2Itisusefultoturntoafitnessconsulantforadvice.Itisdangeroustotakeillegaldrugs.Itisharmfultoskipbreakfast(too)often.Completetheconversationswiththecorrectformsofthephrasesinthebox.31.A:Hello,doctor.Iwanttoloseweight,butIjustcan’tseemtodoit.Whatcanyoudotohelpme?B:Well,first,it’snecessaryto______________whatyoueat.Cutoutallfattyfoodandsugarydrinks,andeatmorefruitandvegetables.2.A:Ireallyneedto_________awaytoexercisemore.Icoulduseafitnessapp,butmyphone’sfull.B:Sodeleteafewfiles.I'msuretheappdoesn’ttakeupmuchspace.beginwithbeincontrolofmakeachoicedecideonmakeupone’smindbeincontrolofdecideon3.A:Beforeexercising,alwaysdoafewwarm-upsto__________.B:Iknow.ButthenIalwaysfeeltootiredtocontinue!4.A:ShouldIgo