Youshouldn'teatmeat.So,theyhavetobegivendrugs.Youdidnothavetoeatthat!Yououghttoeatsomesaladinstead.Weshoulduselandtogrowfoodforpeopleinsteadofcattle.Modalverb(情态动词)Weusewordshaveto,must,shouldandoughttotoshowthatitisnecessaryorimportanttodosomething.Modalverb(情态动词)Youshouldn'teatmeat.So,theyhavetobegivendrugs.Youdidnothavetoeatthat!Weshoulduselandtogrowfoodforpeopleinsteadofcattle.Yououghttoeatsomesaladinstead.Whatformdoweusewhenaverbaftermodalverbs?Weshouldusethebaseform(i.e.,theformusedinthedictionary)ofaverbaftermodalverbsModalverb(情态动词)e.g.Imustleavenow.Ihavetoleavenow.samedifferenthaveto1)forrulesandorders2)havenochoiceobjectivemustsubjective我自己想离开,主观愿望也许我还想坐一会儿,但我还有要事,不得不走了Negativemustnot=somethingisnotalloweddonothaveto=somethingthatisnotnecessaryMusthasnopastform,soweusehadtoinsteadCanyoufindanexampleinthetext?Theanimalsyoueathadtospendtheirlivescrowdedtogetherintinyspaces.Modalverb(情态动词)Weuseshouldandoughttowhenwefeelthatitisimportanttodosomething,ortogiveadvice.Should---强调个人主观看法Oughtto---强调客观因素所以在表示建议的时候,should的语气更强Modalverb(情态动词)Imusthavetoshouldoughttogobacknow.Imustnotdonothavetoshouldnotgobacknow.MustIDoIShouldIgobacknow?Oughttoisnotcommonlyusedinaquestionorinanegative.Modalverb(情态动词)比较must,haveto,和should/oughtto所表示的不同意义Fillingtheblankwithmust,havetoorshould/oughtto1)钢琴老师对某学生说You___practiseatleastanhouraday.2)这个学生然后对他的朋友说I____practiseanhouraday!3)他的朋友会说You_______practiseformorethananhour.musthavetooughtto/shouldHealthTipsVitaminGoodforSourcesApreventingspotsliver(肝),greenvegetablesB1increasinggrowthbeans,pork,fishB2healthyhairmeat,soyabeansChealthyteethandgums,(牙床)healthyskinfruit,vegetablesS1:I'vegotspotsonmyface.S2:ThenyouhavetotakemoreVitaminA.S1:WherecanIgetit?S2:Fromgreenvegetables.HealthTipsVitaminGoodforSourcesApreventingspotsliver(肝),greenvegetablesB1increasinggrowthbeans,pork,fishB2healthyhairmeat,soyabeansChealthyteethandgums,(牙床)healthyskinfruit,vegetablesJumpingDivingsmokingFightingSwimingShoweringIfyouarealifeguardataswimmingpool.Whatwillyousaytothesepeople?Usemustormustnot.ThedailylifeofBen4.30a.m.getup,eatnobreakfast5.00a.m.cleanhouse,beginworking12.00p.m.eatmuchmeatstew(烤肉)andriceforlunch,drinkbeer1.00p.m.takeanapfortwohours3.00p.m.begintrainingagain8.00p.m.eatmeatstewandricefordinner,drinkbeer11.00p.m.gotobedYou______getupsoearly.You_____havebreakfasteverymorning.You_____eatfruitandvegetables.You______drinkbeeratlunch.You_____takealongnapaftereatingsomuch.You____eatdinnerearlier.You_____gotobedearlier.Useshould,shouldnotandoughtto