Unit4 Grammar 語法講義- must和have to以及特殊疑問詞 to do-牛津譯林版八年級英語下冊

Unit4Grammar語法講義---must和haveto以及特殊疑問詞+todo一.must和haveto的區(qū)別I.must表示主語“必須”做某事，強(qiáng)調(diào)說話人的主觀意愿;必須做某事（主觀意愿）mustdosth.禁止做某事mustn’tdosth.例1：—MustIkeepthedooropen?—Yes,youmust.例2：—MustIbringmyhomeworkwhenIcomehere?—No,youneedn’t.—No,youdon’thaveto.II.haveto強(qiáng)調(diào)的是客觀需要，意思是“不得不，得做某事”。不得不做某事（客觀需要）havetodosth.不必做某事don’thavetodosth.haveto有人稱和數(shù)的變化:hasto,hadto,willhaveto。注意：must表示必須，其否定形式為needn’t或don’thaveto，而不是mustn’t。mustn’t表示禁止。二.拓展：情態(tài)動詞的用法情態(tài)動詞用法?？嫉娜N情況：表示可能性、猜測：can（一般表示對客觀真理的猜測，不用于現(xiàn)實事件的猜測）----無否定could（can的過去式）易錯點(diǎn):may（表示對事件的猜測）----否定maynot（可能不）---過去式mightmust（一定）-----否定-can’t（不可能）例1：Therecanbealiensintheouterspace.------表示對科學(xué)真理的猜測例2：HecanbeLily’sfather.----錯，can不用于現(xiàn)實事件的猜測改正：HemaybeLily’sfather.例2：ThereislightinMr.Li’soffice.He_________(一定)beinside.-----mustbe例3：Mr.LiisonbusinessinShanghai,sohe__________(不可能)beathome.---can’tbe例4：他可能不是李老師。HemaynotbeMr.Li.他可能是李老師。HemaybeMr.Li表示請求允許：may,might,can,could,mustn’t.例1:----Might/MayIsmokeinthisroom?----No,youmustn’t.例2：----May/MightItakethisbookoutoftheroom?----Yes,youcan.(No,youcan’t/mustn’t.)表示必須，必要：must一定；needn’t不必；don’thaveto不必。例：----Mustwehandinourexercisebookstoday?----Yes,youmust.----No,youdon’thaveto/youneedn’t. 練習(xí)1.Mike,you______playwithfire.You__________burnyourself.A.won’t;can’t B.mustn’t;may C.don’thaveto;must D.havegotto;shouldn’t2.---Where’smyumbrella?---It’sfinetoday.You____________takeanumbrellawithyou.A.can’t B.needn’t C.mustn’t D.shouldn’t3.I’msorry.I___________gonow.Myfathertoldmeonthephonethatmymotherwasill.A.must B.haveto C.may D.think4.—MustIfinishreadingthebookfirst?—No,you_______.Youmayfinishittomorrow.A.can’tB.mustn’tC.don’thavetoD.shouldn’t5.Allthestudents_________knowshoutingattheelderlyisimpolite.A.can B.couldC.must D.need6.--Where’smyumbrella?--It’sfinetoday.You______takeanumbrellawithyou.A.can’tB.needn’tC.mustn’tD.shouldn’t7.Mr.Collins________liketea.Hemakesacupofteaforhimselfeverymorning.A.must B.may C.can't D.mustn't8.—TheCCTVMarch15thEveningPartyshowedthatthesnack"spicystrip"whichchildrenlikeeatingispoisonous(有毒的).—Yes.Something______bedonetomakeproducerspayattentiontofoodsafety.A.need B.might C.may D.must9.Tomyjoy,we______gotothebank.Maryhaslentussomemoney.A.shouldn't B.needn’t C.couldn't D.wouldn't10.Healwaysmeanswhathesays.There______beareasonwhyhedidn'ttellthetruth.A.Must B.should C.may D.can11.--It'ssaidthatdrinkingcoffeecausescancer.DoIgiveitup?--Relax!NoteverythingonWeChatistrue.Infact,acoffeeadaykeepsthedoctoraway.A.mustB.mayC.canD.haveto三.特殊疑問詞+todo用法：用于句中由來：來源于賓語從句，是賓語從句的簡略形式當(dāng)know,remember,decide,forget等動詞后接賓語，并且從句主語與主句主語一致，從句可以簡化成“疑問詞+不定式”結(jié)構(gòu)。Idon’tknowhowIshoulddothework.=Idon’tknowhowtodothework.IhavedecidedwhatIshoulddonext.=Ihavedecidedwhattodonext.賓語從句的主語和主句的間接賓語一致，也可簡化。CouldyoutellmehowIcangetthere?=Couldyoutellmehowtogetthere?練習(xí)Theyknow___________tomeetat8:00tomorrow.(where,when)Canyoutellus_________totalkto?(who,where)Doyouknow_________tofixthecomputer?(who,how)Sandywantstoknowwhere_________(ask)foradvice.Myquestioniswhen__________(start).Bequiet!Wearetalkingaboutwhattime________(meet)atTaiheShoppingMall.It’stoodifficult.Idon’tknowhow__________(answer)it.Ireallydon’treallyknowwhen_________________(begin)themeeting.Ireallydon’t