人教版選擇性必修三DiscoverUsefulStructuresTheinfinitiveoftheverbusedasthesubjectUnit2HealthyLifestyle杭州二中許麗君1.EnabletheSstomastertheusageoftheinfinitiveoftheverbasthesubject2.EnabletheSstousetherelevantgrammarflexiblyandauthenticallyintherealsituation.TeachingGoals

單元語法探究Lookatthefollowingsentencesandpayattentiontotheitalicizedinfinitives.Findmoreinfinitivesinthereadingpassage,andtelltheirmeaningsandfunctions.1.Tochangebadhabits

isnevereasy.2.Ittookthesurgeonthreehourstofinishmymother’slingsurgery.3.Tojointhepeople’sLiberationArmy,itisrequiredformentoshaveofftheirbeards.4.Itwasnotpolitetodisturbyourneighborswithloudmusiclastnight.Moreinfinitivesinthereadingpassage1….itcanbeeasyforsomeofthemtoformbadhabits.2.Afterall,itisnoteasytobreakbadhabits.Theirmeaningsandfunctions動詞不定式在句中做主語，有時為了保持句子的平衡，避免頭重腳輕，常用it做形式主語，而真正地主語放在句子的末尾。比如第2；3；4例句。Grammaranalysis

TheInfinitive

(todo……)Whatformsdoesinfinitivehave?Basicstrategy:

Addtense時態(tài)andvoice語態(tài)

into“todo”structure!不定式的時態(tài)和語態(tài)：不定式主動被動

一般towritetobewritten

進行tobewriting

完成tohavewrittentohavebeenwritten

完成進行tohavebeenwriting

Grammaranalysis4.Itisimportant

______Tomtogetthatjob.Itiskind______youtohelpmewithmyhomework.1.______(talk)withhimisagreatpleasure.2.______(help)othersisourduty.TotalkTohelpItisourdutytohelpothersforof不定式作主語：3.Itiseasy______________________(學(xué)生讀)forthestudentstoread.GrammaranalysisTodoBe的單數(shù)形式Infinitiveasthesubjectofthesentence:不定式作主語Example

1:Tohelpothersis

ourduty.主語系動詞:表語Example

2:Togetgoodgradesrequires

alotofhardwork.Todo主語謂語動詞單數(shù)形式賓語GrammaranalysisInfinitiveastherealsubjectofthesentence:_________(help)othersisourduty.TohelpIt

is

ourdutytohelpothers.形式主語It系動詞Be的單數(shù)形式表語真正主語TodoIt(形式主語)~todo（真正主語）Grammaranalysis不定式作主語和動詞-ing形式作主語的區(qū)別：動詞-ing形式和不定式作主語,都是說明一個內(nèi)容。不定式通常表示一個將來的、具體的內(nèi)容;但是,而動詞-ing形式則表示一種經(jīng)常性的、習(xí)慣的或抽象的概念。Tolookafterchildrenisherjobtoday.她今天的工作是看孩子。Lookingafterchildrenisherwork.她的工作是照顧孩子。Grammaranalysis不定式作主語，it做形式主語的常見結(jié)構(gòu)：Itis+adj.+(forsb)todoItiseasyformetolearnhowtodrive.學(xué)開車對我來說很輕松。Itis+adj.+(ofsb)todoItiscleverofyoutoapplyfortheposition.你申請這個職位真是明智的。Itis+n.+todosth(anhonour,ourduty,apity,ashame)Itisourdutytotakecareofyou.照顧你是我們的責(zé)任。Ittakes/tooksbsometimetodosth.Ittookmehalfanhourtodomyhousework.我花了半個小時做家務(wù)。GrammaranalysisGrammaranalysis疑問詞+不定式做主語可用于該結(jié)構(gòu)的疑問詞疑問代詞：who，whom，what，which疑問副詞：when，where，how常接該結(jié)構(gòu)的動詞：know，see，decide，tell，ask，consider，explain，learn，wonderHowtoconstructthetheoreticalframeworkisveryimportant.怎樣構(gòu)建理論框架很重要。（作主語）Whentostartdevelopingsuchavaccineisthequestion.問題是何時開始研制這種疫苗。（作主語）Wheretofindthatpatrioticyoungmanisaheadacheforme.到哪里去找那個愛國的年輕人令我頭疼。（作主語）練習(xí)：1.Whenandwhere

（vote）hasn’tbeendecided.2.

__________________（何時裝修）thehousehasn’tbeendecidedtovoteWhentodecorate3.如果要說明不定式表示的動作是誰做的，可以在不定式前加一個由for/of引起的短語,構(gòu)成_______________。2.不定式作主語時,可以用it作_______________.Itis+adj+forsbtodo……5.Itis+adj+ofsbtodo………(adj:kind,good,nice,wise,unwise,clever,silly,stupid,foolish,careless,rude,polite,naughty)（修飾人品形容詞）（修飾物的形容詞）1.單個不定式作主語，謂語動詞_____________單數(shù)形式主語不定式的復(fù)合結(jié)構(gòu)Summary(adj.:easy,difficult,comfortable,pleasant,light,dangerous，tiresome,interesting,heavy,fit)單句語法填空（1）Sometimesit’sbetter

（remain）silent.（2）Although

isahardtasktoprotectourenvironment，wecan’thelpbutgoahead.

（3）

（control）theairpollutionisnecessary.（4）Itwasfoolish

himtoendangerhislifeinthatway.（5）Don’tyouthinkitisrude

himtoaskaladyherage?（6）Itisdifficult

himtoliveonsuchasmallsalary.toremainitTocontrol/ControllingofofforPractice完成句子（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. itisimpoliteofyoutoaskIt’sourdutytodefendIttookmehalfanhour PracticeJointhewordstomakefullsentencesusingtheinfinitive.1.important/avoid/passivecigarettesmoking.2.willtake/nutritionspecialist/abalanceddietmenu/make/anhour/foryou.3.useful/turnto/fitnessconsultant/foradvice4.illegal/dangerous/take/drugs5.harmful/skipbreakfast/oftenPractice1.important/avoid/passivecigarettesmoking.Itisimportanttoavoidpassivecigarettesmoking.2.willtake/nutritionspecialist/abalanceddietmenu/make/anhour/foryou.Itwilltakeanutritionspecialistanhourforyoutomakeabalanceddietmenu.3.useful/turnto/fitnessconsultant/foradviceItisusefultoturntofitnessconsultantforadvice.4.illegal/dangerous/take/drugsItisillegalanddangeroustotakedrugs.5.harmful/skipbreakfast/oftenItisharmfultooftenskipbreakfast.Practicecompletetheconversationswiththecorrectformsofthephrasesinthebox.1.A:Hello,doctor.Iwanttoloseweight,butIjustcan'tseemtodoit.Whatcanyoudotohelpme?B:Well,first,it'snecessaryto______________whatyoueat.Cutoutallfattyfoodandsugarydrinks,andeatmorefruitandvegetables.2.A:Ireallyneedto_____________awaytoexercisemore.Icoulduseafi