高中英语-Unit Two Healthy eating教学课件设计

Unit2HealthyeatingPeriod3Grammar学案导学语法专项:情态动词oughtto,haveto及need的

用法；情态动词+havedone结构

一．Teachingaims:1.Canusemodalverbs:oughtto,havetoandneedcorrectly.2.Canusemodalverb+havedonecorrectly.二．Difficultandkeypoints:1.Theusagesofoughtto,havetoandneed2.Theusagesofmodalverb+havedone三.Teachingmethods:PapersVideos四.Teachingprocedures:Lead-inpresentationsummary课前自主落实翻译下列句子：1.到现在他的餐馆应该满人了。Bynowhisrestaurant____________befullofpeople.2.如果李昌没有像往常一样来他的餐馆吃饭一定发生了可怕的事情。

Somethingterrible__________________________ifLiChangwasnotcomingtoeatinhisrestaurantashealwaysdid.可能发生了什么呢？What___________________________?

oughttomusthavehappenedcouldhavehappened课中探究学习一.oughtto表示义务责任或建议劝告，后跟动词原形，无人称，数和时态变化，意为：应当，应该eg.1.Humansoughttostoppollutingnature.

即时训练：He_____________obeyhisparents.

oughtto考点提示：1.oughtto否定形式为oughtnot(oughtn’t)to;一般疑问句形式将ought置于主语前，肯定回答常用oughtto,否定回答常用don’thaveto或needn’t.eg.1.Yououghtn’ttomakethiskindofmistakeagain.即时训练：_______he______seethedoctor?Yes,heoughtto./No,hedoesn’thaveto.(he__________.)2.oughttohavedone相当于shouldhavedone表示本应该做某事而事实上未做

oughtn’ttohavedone相当于shouldn’thavedone表示本不该做某事而实际上却做了eg.1.Youarelate.Yououghtto/shouldhavearrivedfiveminutesearlier.即时训练:Sheisveryangry.We____________/shouldn’thavetoldherthebadnews.Oughttoneedn'toughtn'tto重点提示：一般来说oughtto和should可互换，但oughtto语气略强，另表示出于法令规则，行为准则，道德责任等客观情况而应该做某事；而should则强调主观看法。eg.1.Thereoughtnottobesomuchnoiseinahospital.即时训练:Youaremistaken,I_________say.(据我看）二．haveto表客观上的必要性，常被看作情态动词，意为不得不，有人称，数和时态变化；其疑问式和否定式由助动词do/don’t构成。eg.1.Ababyhastosleepmorethan12hoursaday.即时训练:Itwasrainingoutside;We___________stayathome.shouldhadto考点提示：don’thaveto表没有义务或必要做某事，意为不必，常可回答must提问的疑问句。而must的否定式mustn’t指说话人的主观命令或强烈劝告或禁止。eg.1.Thereisplentyoftime.Youdon’thavetohurry.即时训练:1.Mustwehandinourplanthisweek?No,youdon’thaveto.(No,you_____________.)2.You_____________drivewithoutalicense.needn'tmustn't

三.need作为情态动词，主要用于否定句，疑问句和条件从句中

eg.Whyneedyougotoday?

即时训练:________wemakethetest?-No,weneedn’t.Need重点提示：由need引起的一般疑问句，肯定回答用must/haveto,否定回答用needn’teg.Needhedoitallatonce?Yes,hemust./No,he________(doesn’thaveto).needn't考点提示：needn’thavedone表本没必要做而做了eg.1.Iactuallyneedn’thaveboughtsomuchwine----onlythreepeoplecame.即时训练:I_____________________(take)abathforIdiditlastnight.needn'thavetaken归纳拓展:need既可作情态动词也可做实义动词。作实义动词同其他实义动词一样，有人称，数和时态的变化，构成否定句和疑问句时要用助动词don't/doesn't,do/doeseg.1.Thereistoomuchhousework,sohermotherneedssomehelp.即时训练:Lastnightshe_________hishelptofinishthework,buthewasn’tathome.needed四.情态动词+havedone表对过去的推测

构成

主要用法

句式

典型例句musthavedone对过去已发生行为进行推测，意为:想必，准是，一定作了某事

肯定句Youmusthavegonetobedlatelastnight.can/couldhavedone对过去发生行为的怀疑和不肯定否定句疑问句Hecannothaveforgottenit.may/mighthavedone对过去已发生行为进行推测，意为:也许，或许肯定句否定句It’stoolate.Ithinkhemayhavegonetobed.情态动词+havedone表后悔，责备或遗憾couldhavedone表过去没有实现的可能性，意为:本来可以

肯定句Theaccidentcouldhavebeenavoided.mighthavedone表本来可以做某事，含轻微责备

肯定句Youmighthavegivenhimmorehelp,thoughyouwerebusy.oughtto/shouldhavedone表本该做某事而实际上未做

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

否定句Iactuallyneedn’thaveboughtsomuchwine----onlythreepeoplecame.巩固练习1.I__________havewatchedthatmovie-----it’llgivemehorribledreams.(2010.山东高考）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巩固练习

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