Unit2HealthyeatingPeriod3Grammar學(xué)案導(dǎo)學(xué)語法專項:情態(tài)動詞oughtto,haveto及need的

用法；情態(tài)動詞+havedone結(jié)構(gòu)

一．Teachingaims:1.Canusemodalverbs:oughtto,havetoandneedcorrectly.2.Canusemodalverb+havedonecorrectly.二．Difficultandkeypoints:1.Theusagesofoughtto,havetoandneed2.Theusagesofmodalverb+havedone三.Teachingmethods:PapersVideos四.Teachingprocedures:Lead-inpresentationsummary課前自主落實翻譯下列句子：1.到現(xiàn)在他的餐館應(yīng)該滿人了。Bynowhisrestaurant____________befullofpeople.2.如果李昌沒有像往常一樣來他的餐館吃飯一定發(fā)生了可怕的事情。

Somethingterrible__________________________ifLiChangwasnotcomingtoeatinhisrestaurantashealwaysdid.可能發(fā)生了什么呢？What___________________________?

oughttomusthavehappenedcouldhavehappened課中探究學(xué)習(xí)一.oughtto表示義務(wù)責(zé)任或建議勸告，后跟動詞原形，無人稱，數(shù)和時態(tài)變化，意為：應(yīng)當(dāng)，應(yīng)該eg.1.Humansoughttostoppollutingnature.

即時訓(xùn)練：He_____________obeyhisparents.

oughtto考點提示：1.oughtto否定形式為oughtnot(oughtn’t)to;一般疑問句形式將ought置于主語前，肯定回答常用oughtto,否定回答常用don’thaveto或needn’t.eg.1.Yououghtn’ttomakethiskindofmistakeagain.即時訓(xùn)練：_______he______seethedoctor?Yes,heoughtto./No,hedoesn’thaveto.(he__________.)2.oughttohavedone相當(dāng)于shouldhavedone表示本應(yīng)該做某事而事實上未做

oughtn’ttohavedone相當(dāng)于shouldn’thavedone表示本不該做某事而實際上卻做了eg.1.Youarelate.Yououghtto/shouldhavearrivedfiveminutesearlier.即時訓(xùn)練:Sheisveryangry.We____________/shouldn’thavetoldherthebadnews.Oughttoneedn'toughtn'tto重點提示：一般來說oughtto和should可互換，但oughtto語氣略強(qiáng)，另表示出于法令規(guī)則，行為準(zhǔn)則，道德責(zé)任等客觀情況而應(yīng)該做某事；而should則強(qiáng)調(diào)主觀看法。eg.1.Thereoughtnottobesomuchnoiseinahospital.即時訓(xùn)練:Youaremistaken,I_________say.(據(jù)我看）二．haveto表客觀上的必要性，常被看作情態(tài)動詞，意為不得不，有人稱，數(shù)和時態(tài)變化；其疑問式和否定式由助動詞do/don’t構(gòu)成。eg.1.Ababyhastosleepmorethan12hoursaday.即時訓(xùn)練:Itwasrainingoutside;We___________stayathome.shouldhadto考點提示：don’thaveto表沒有義務(wù)或必要做某事，意為不必，常可回答must提問的疑問句。而must的否定式mustn’t指說話人的主觀命令或強(qiáng)烈勸告或禁止。eg.1.Thereisplentyoftime.Youdon’thavetohurry.即時訓(xùn)練:1.Mustwehandinourplanthisweek?No,youdon’thaveto.(No,you_____________.)2.You_____________drivewithoutalicense.needn'tmustn't

三.need作為情態(tài)動詞，主要用于否定句，疑問句和條件從句中

eg.Whyneedyougotoday?

即時訓(xùn)練:________wemakethetest?-No,weneedn’t.Need重點提示：由need引起的一般疑問句，肯定回答用must/haveto,否定回答用needn’teg.Needhedoitallatonce?Yes,hemust./No,he________(doesn’thaveto).needn't考點提示：needn’thavedone表本沒必要做而做了eg.1.Iactuallyneedn’thaveboughtsomuchwine----onlythreepeoplecame.即時訓(xùn)練:I_____________________(take)abathforIdiditlastnight.needn'thavetaken歸納拓展:need既可作情態(tài)動詞也可做實義動詞。作實義動詞同其他實義動詞一樣，有人稱，數(shù)和時態(tài)的變化，構(gòu)成否定句和疑問句時要用助動詞don't/doesn't,do/doeseg.1.Thereistoomuchhousework,sohermotherneedssomehelp.即時訓(xùn)練:Lastnightshe_________hishelptofinishthework,buthewasn’tathome.needed四.情態(tài)動詞+havedone表對過去的推測

構(gòu)成

主要用法

句式

典型例句musthavedone對過去已發(fā)生行為進(jìn)行推測，意為:想必，準(zhǔn)是，一定作了某事

肯定句Youmusthavegonetobedlatelastnight.can/couldhavedone對過去發(fā)生行為的懷疑和不肯定否定句疑問句Hecannothaveforgottenit.may/mighthavedone對過去已發(fā)生行為進(jìn)行推測，意為:也許，或許肯定句否定句It’stoolate.Ithinkhemayhavegonetobed.情態(tài)動詞+havedone表后悔，責(zé)備或遺憾couldhavedone表過去沒有實現(xiàn)的可能性，意為:本來可以

肯定句Theaccidentcouldhavebeenavoided.mighthavedone表本來可以做某事，含輕微責(zé)備

肯定句Youmighthavegivenhimmorehelp,thoughyouwerebusy.oughtto/shouldhavedone表本該做某事而實際上未做

肯定句否定句Youarelate.Yououghttohavearrivedfiveminutesearlier.needn’thavedone表做了本來不必做的事

否定句Iactuallyneedn’thaveboughtsomuchwine----onlythreepeoplecame.鞏固練習(xí)1.I__________havewatchedthatmovie-----it’llgivemehorribledreams.(2010.山東高考）A.shouldn’tB.needn’tC.couldn’tD.mustn’t 2.Mark_______havehurried.Afterdrivingattopspeed,hearrivedhalfanhourearlier.(2010.天津高考）A.needn’tB.wouldn’tC.mustn’tD.couldn’t3.Jackdescrisbedhisfather,who_______abraveboymanyyearsago,asastrong-willedman.(2010.安徽高考）A.wouldbeB.wouldhavebeenC.mustbeD.musthavebeenADA鞏固練習(xí)

4.You________buyagift,butyoucanifyouwantto.(2010.湖南高考）A.mustB.mustn’tC.haveD.don’thaveto5.You________parkhere!It’sanemergenceexit.(2010.重慶高考）A.wouldn’tB.needn’tC.couldn’tD.mustn’t6.___Sorry,ProfessorSmith.Ididn’tfinishtheassignmentyesterday.__