提建议语气：hadbetter〈should〈oughtto语气最强。否定式：hadbetternot,shouldnot,oughtnotto。should/oughtto用法小结1.应该，应当•我放进新的电池了，收音机应该能用了。Ihaveputinnewbatteries,sotheradiooughttoworknow.(按道理)•你不应该这样做。（我认为）Youshouldnotdoso.2.应当，应该（表示劝告和建议）•你应该多运动，对你身体好。Youshould/oughttodomoreexercises.Itwilldoyougood.•你发烧了，应该去看医生。Youhaveafever.Youshould/oughttogotoseethedoctor.3.想必一定，照理应该(推测)•这个时候他该起床了。Heshould/oughttobeupnow.•五十块钱应该购买这本书了。Fiftydollarsshould/oughttobeenoughtobuythisbook.Oughtto/should在多数情况下可以互换。但:1)oughtto语气重，含有“按道理应该”之意；2)should表示自己的主管看法。3)如果反映客观情况或涉及法律，义务和规定时一般用oughtto.4)疑问句中通常用should.Choosethebestanswertothequestion.1.Theflowerisdead.I______ityesterday.A.shouldwaterB.mustwaterC.shouldhavewateredD.mustn’thavewatered2.WhattimeoughtI______?A.arrivedB.arrivingC.arriveD.toarrive3.He______speaktohismotherlikethat.A.oughtnottoB.doesn’toughttoC.notoughttoD.oughttonot√√√hadbetterdo：“最好”,•你最好别说那样的话。You’dbetternotsaythat.•我们最好带一把伞吧?Hadn’twebettertakeanumbrella?•我最好先作一下自我介绍。Ihadbetter(IthinkIshould)beginbyintroducingmyself.•He________________________________stopsmoking.•You_____________________________________________leaveababyaloneinthehouse.They___________________havecalledthepolice.should/oughtto/hadbettershould/oughttoshouldnot/oughtnotto/hadbetternot•学生们应遵守校规。Thestudentsoughttoobeytheschoolrules．他是七点钟出发的，这会儿总应该到了。Hestartedatseven,soheoughttobeherenow．Practice1.----Writetomewhenyougethome.----______.A.ImustB.IshouldC.IwillD.Ican2.----Willyoustayforlunch?----Sorry,______.Mybrotheriscoming.A.Imustn’tB.Ican’tC.Ineedn’tD.Iwon’t√√3.----Didyouscoldhimforhiscarelessness?----Yes,but______.A.I’drathernotto.B.I’drathernothavedoneso.C.Ishouldn’tdo.D.I’dbetternotdo.√Ishouldnothavedoneso.4.Youdidn’tgotothepartyyesterday,orI______you.A.wouldseeB.couldseeC.mighthaveseenD.mightsee5.Lookwhatyouhavedone.You______havebeencareful.A.shouldB.canC.mustD.may√√6.Putonmoreclothes.You______befeelingcoldwithonlyashirton.A.canB.couldC.wouldD.must7.Theplantisdead.I______itmorewater.A.willgiveB.wouldhavegivenC.mustgiveD.shouldhavegiven√√8.Ididn’thearthephone.I______asleep.A.mustbeB.musthavebeenC.shouldbeD.shouldhavebeen9.Hewasbusyorhe______hermorehelp.A.hadgivenD.wouldgiveC.couldhavegivenD.give√√must的用法1.表示主观的义务和必要,意思为“必须……，得……，要……”；由must引起的疑问句,否定回答要用needn’t或don’thaveto,意思是“不必”；•Youmustgetupearly.•Wemustfindagoodmethodtolearncomputerwell.—MustIfinishthetaskrightnow?我现在必须完成这个工作吗？—Yes,youmust./Yes,youhaveto.—Yes,please./I’mafraidso。是的。(—No,youneedn’t./No,youdon’thaveto.不，不必。)must的否定形式mustn’t表示禁止，意思是“不能，不许”。•没有得到允许，你不能来这儿。Youmustn’tcomeherewithoutpermission.•我们不该浪费时间。Wemustn’twasteourtime.----MayItakethismagazineout?----No,youmustn’t.2.表示肯定的，又根据的，有把握的推测，用于肯定句中，意思为“一定是,必然……”。否定形式：can’t.注意must表示推断或猜测的几种情况:•Itmustbeeleveno’clocknow./Hemustbecrazy.•Yoursistermustbeadoctorinthishospital.（现在的猜测）•你姐姐一定不是这家医院的医生，因为我从来...
