Chapter-7下Modal-Auxiliaries情態(tài)助動詞

現(xiàn)代英語語法Chapter7ModalAuxiliaries情態(tài)動詞(下)7.3Shouldandoughtto7.3.1Should1.表推測(假設(shè)性推斷)eg:Itshouldbethepostmanatthedoor.表示推測時，might<may<could<can<should<<would<will<must2.非推測(義務(wù))"應(yīng)該做的事"eg:Youshouldbemorepatient.3.should與完成時連用，表示對過去事件狀態(tài)的假設(shè)。eg:Youareright.Ishouldhavelistenedtoyou.4.推定性should.〔P174最后一段〕a.在表示“情感”或“觀點”的名詞或形容詞如amazed,annoyed,grateful,strange等引導(dǎo)的that從句中，使用should+v原形表示虛擬語氣。eg:It'sstrangethatsheshouldwearareddress.好奇怪，她竟然穿了件紅裙子。b.推定性的should也可以用在if從句中，表示假設(shè)。eg:Ifheshouldbefoundguilty,he'llloseeverything.如果被人發(fā)現(xiàn)他犯罪，他將失去一切。7.3.2Oughtto在下面這些情況下should=oughtto1.表推測(假設(shè)性推斷)eg:Itshould/oughttobethepostmanatthedoor.2.表非推測(義務(wù))eg:Youshould/oughttobemorepatient.7.3.3Shouldvsoughtto1.一般情況下should可以與oughtto互換，但是在疑問句和否認(rèn)句中should更加常用。eg:ShouldIgiveyouacallwhenIhearthenews?Youshouldn'tbesoimpatient.2.表示義務(wù)時，should強調(diào)主觀性，根據(jù)說話者的意愿作出要求；oughtto強調(diào)客觀性，根據(jù)道德標(biāo)準(zhǔn)作出要求。eg:Youshouldtakecareofyourparents.(說話人意愿)Yououghttotakecareofyourparents.(道德要求)7.4Must,needandhave(got)to這幾個詞都表示“必須；必要”。7.4.1Must1.表推測。(肯定性/不可防止的推斷)eg:JohnmustbeinNewYorknow.Shemusteattoomuch,orshewouldn'tbesofat.2.表非推測。(必要性/強制/義務(wù))eg:Imustpayforthebill.(必要)Youmustfinishyourworkbeforenoon.(強制)Youmustcleanupyourownroom.(義務(wù))3.表示推測時，must是最高強度的可能性，多用于現(xiàn)在和過去時態(tài)。eg:Itistwelve.Hemustbeatworknow.(現(xiàn)在)SoyouknowLuxun.Youmusthavereadalot.(過去)4.表示推測時，must一般只用于肯定句，不用于否認(rèn)和疑問句。can表推測多用于否認(rèn)句和疑問句。eg:JohnmustbeinNewYorknow.CanJohnbeinNewYorknow?Johncan'tbeinNewYorknow.5.must表示強制或義務(wù),可用于肯定，疑問和否認(rèn)。a.主觀性。說話人強加的命令。eg:Youmustdoasyouraretold,oryougetfired.b.客觀性。外部或環(huán)境強制力。eg:Candidatesmustansweratleastfiveoutoftenquestion.候選人必須至少答復(fù)一半問題。6.表推測對must提問時的答復(fù)eg:——MustIhandinmyhomeworktomorrow?——Yes,youmust.——No,youneedn't.should/oughtto與mustshould/ought“應(yīng)該”，表示具有多個選擇。must“必須”，表示只有一個選擇。eg:Youshould/oughttobepolitetoladies.Youmustbepolitetoladies.7.4.2Needneed是個非肯定性的助詞，多用于否認(rèn)句和疑問句，希望得到否認(rèn)答復(fù)。(尋求否認(rèn)必要性的答案)1.非推測性(必要性)eg:Youneedn'tcomeifyoudon'tlikeit.——Needyouseethedoctoragain?——Yes,Imust./No,Ineedn't.2.如果句中有否認(rèn)副詞，可以使用need的肯定形式。eg:Heseldomneedcookhisownmeals.I'mnotsurewhetherIneedgo.3.Need更多用于實義動詞，作謂語動詞，有人稱和數(shù)的變化，這時可以用在肯定句中?！睵179第一句〕eg:Ineedtofinishmyhomeworktonight.Doesheneedtogotoschool?4.Need表必要性的疑問句，對其答復(fù)：eg:——NeedIgowithyou?——Yes,youmust.——No,youneedn't./No,youdon'thaveto.5.needn'thavedone,表示"過去的某件事沒必要做(已經(jīng)做了)"；eg:Youneedn'thavecleanedtheroom.你沒有必要幫我清掃房間，我自己會做。(已經(jīng)清掃)didn'tneedtodosth表示“沒有必要做某事(沒做)”eg:Youdidn'tneedtocleantheroom.你不用清掃房間，我自己會做。(未清掃)7.4.3Have(got)to這兩個詞不是情態(tài)助詞，相當(dāng)于情態(tài)動詞must.1.表推測(肯定/不可防止的推測)eg:Peterhas(got)tobeill.2.表非推測(必要性/強制/義務(wù))eg:Ihavetobeatofficeat8:30.3.haveto比較正式，有非謂語形式變化，表示客觀必要性；havegotto較少見，多表示主觀必要性，相當(dāng)于must.eg:Ihavetogotoseethedoctortoday.(很不舒服，客觀)Youmustgotoseethedoctor.(說話人意愿，主觀)7.5Dare1.情態(tài)動詞dare表示"敢于做...",用法跟need很相似，一般使用在非肯定句中，即多用于否認(rèn)和疑問句。eg:Dareyouaskhimeagain?你敢再問他一次嗎？Idarenotaskhimagain.2.dare作為實義動詞時，接動詞不定式，即dare(to)dosth.這里的to可以省略.eg:Hedoesnotdare(to)askhimagain.Don'tyoudare(to)touchher!你敢碰她試試！總結(jié)：情態(tài)動詞提問時的答復(fù)1.can疑問句:肯定can,否認(rèn)can't2.may疑問句:肯定may,否認(rèn)mustn't3.will疑問句:肯定will,否認(rèn)willnot或won't4.must疑問句:肯定must,否認(rèn)needn't/don'thaveto5.need疑問句:肯定must,否認(rèn)need't.1.—What’sthematterwithyou?—Oh,I’mnotfeelingwellinthestomach.I______somuchfriedfishjustnow.A.shouldn’teat B.mustn’thaveeatenC.shouldn’thaveeaten D.mustn’teat解析：C。shouldn’thavedone表示“本不該做……，但實際上卻做了2.Youarelateforschooltoday.You______toschoolearlier.A.oughttocome

B.shouldhavecomeC.oughthavecomeD.shouldcome解析：B。shouldhavedone表示“過去某件事應(yīng)該做而實際上沒有做”，此處含有責(zé)備之意，也可用oughttohavecome。3.Shemustbehungry,______she?A.isn’tB.needn’tC.doesn’tDwon’t解析：A。反意疑問句中，陳述局部的must表示對現(xiàn)在情況推測時，附加疑問句中通常依據(jù)must后面的動詞形式確定助動詞。4.______youpleasetellmethewaytothepostoffice?A.MustB.NeedC.WouldD.Should解析：C。Wouldyouplease...？是向?qū)Ψ教岢稣埱蠡蛟儐枙r常用的婉轉(zhuǎn)而有禮貌的句型。5.Itisimportantthatwe______learnhowtodrive.A.havetoB.shouldC.needD.shall解析B。在Itisimportant/impossible/necessarythat...句型中，that從句的謂語用“(should+)動詞原形”。6.Ithasbeenannouncedthatcandidates_______remainintheirseatsuntilallthepapershavebeencollected.A.canB.willC.mayD.shall解析：D。在規(guī)章中告誡應(yīng)考者，在收完所有試卷前“必須”留在教室里。7.Withsom