情態(tài)動(dòng)詞小結(jié)

情態(tài)動(dòng)詞(modalverbs)情態(tài)動(dòng)詞在英文中主要用來表示說話人的看法、態(tài)度等。情態(tài)動(dòng)詞特點(diǎn)：1）各個(gè)情態(tài)動(dòng)詞自身都有一定的詞義。2）情態(tài)動(dòng)詞不能在句中獨(dú)立擔(dān)當(dāng)謂語。3）情態(tài)動(dòng)詞在句中不受任何人稱,性,數(shù)變化的影響。4)情態(tài)動(dòng)詞后接的不定式（除ought,used,have外）都不帶to，即接動(dòng)詞原形。5)情態(tài)動(dòng)詞彼此之間是互斥的，兩兩不能在一起。情態(tài)動(dòng)詞的類型：1）只作情態(tài)動(dòng)詞的有：must,can(could),may(might),oughtto2)可作情態(tài)動(dòng)詞也可作實(shí)義動(dòng)詞的有：need,dare3)可作情態(tài)動(dòng)詞也可作助動(dòng)詞的有：shall(should),will(would)4)具有情態(tài)動(dòng)詞某些特征的有：have(had)to,usedto1。情態(tài)動(dòng)詞的形式：主要詞義現(xiàn)在形式過去形式肯定式否定式肯定式否定式能力，容許cancannot/can'tcouldcouldnot/couldn't允許，可能maymaynot/mayn'tmightmightnot/mightn't必須，一定mustmustnot/mustn't不得不，必須havetodon'thavetohadtohadnotto/hadn'tto會，應(yīng)該shallshallnot/shan'tshouldshouldnot/shouldn't想，要，愿，能willwillnot/won'twouldwouldnot/wouldn't敢daredarenot/daren'tdareddarednot/daren't應(yīng)該oughttooughtnotto/oughtn't需要needneednot/needn't（過去）常常usedtousednotto/usedn'tto/didn'tuse(d)to最好，還是…好hadbetterhadbetternot/'dbetternot2.表示具體事情實(shí)際發(fā)生的可能性：詞形肯定式否定式疑問式must必然，必定//will很可能，大概不會，不該會……嗎？would可能性比will小語氣比won’t弱語氣比will弱should確定或可能合乎理想的情況或結(jié)果//oughtto說話者有較大試探性（含義同should）//can（客觀的、理論上的可能性）不可能有可能嗎？could可疑、微弱的可能不可能語氣比can弱may或許，也許，也未可知，也說不定可能不/might比may還弱比maynot還弱/3．情態(tài)動(dòng)詞+havedone的用法情態(tài)動(dòng)詞+完成式用法例句musthavedone表示對過去行為的肯定推測，意為“一定/想必/準(zhǔn)是”Itmusthaverainedlastnight,fortheroadwasquitemuddy.Thelightswereout.Theymusthavebeenasleep.Can...havedonecannothavedone表示對過去發(fā)生的行為的懷疑和不肯定，用在否定句和疑問句中,“可能”Theboycannothavefinishedthebooksosoonbecauseitisdifficulteventoanadult.Canhehaveplayedmeatrick?couldhavedone可用于肯定句，1，表示過去能做而沒做的事，2，推測過去的行為“可能已經(jīng)”Youcouldhavedonebetter,butyouweretoocareless.IsawMr.Whitejustnow.Hecouldn'thavegonetoLondon.may/mighthavedone用于肯定句和否定句，推測過去的行為“可能已經(jīng)”Hemayhavereceivedtheletterlastyear.Hemaynothavefinishedthework.ItmighthavebeenlastOctober.mighthavedone過去應(yīng)該做而沒做的事：“本來可能”Youshouldnothaveswuminthatsea.Youmighthavebeeneatenbyfish.shouldhavedone/oughttohavedone應(yīng)該做的事而沒做，否定式表示某行為不該發(fā)生卻發(fā)生了Youshouldhavecometothemeetingearlier.YououghttohavedonethisexerciseMorecarefully.Sheshouldn'thaveleftthehospitalsosoon,forshehadnotyetrecovered.Heoughtnottohavetreatedhisparentslikethat.needn'thavedone作了本來不必去做的事Youneedn'thavewateredtheflowers,foritisgoingtorain.hadbetterhavedone用于事后的建議，含輕微責(zé)備的口吻，“當(dāng)時(shí)最好做了某事”Youhadbetterhavestartedearlier.Youhadbetternothavescoldedher.wouldratherhavedone表示“當(dāng)時(shí)寧愿做了某事”，含后悔之意Iwouldratherhavetakenhisadvice.Iraisedobjectionsatthemeeting,butnowIwouldrathernothavedonethat.4.對情態(tài)動(dòng)詞的提問1）MayIwatchTVaftersupper?please.youcan't.certainly.youmustn't.Yes,surely.No,you'dbetternot.ofcourse.maynot.2）Mustwedonow?,youmust.youneedn't.Yes,youhaveto.No,youdon'tneedto.Youdon'thaveto.3)NeedItypethisletteragain?Yes,youmust.No,youneedn't.youhaveto.5．表示請求、允諾、允許：1）向?qū)Ψ秸埵净蛱岢鼋ㄗh(1)“Shall/May(might)/Can(could)I/we…?(2)Shallhe/she/they…?(3)Would/Willyou…?2）could/might/would/;should表委婉的功能,(不可用could/might回答)eg.---CouldIuseyourbiketomorrow?---Yes,youcan/may.(No,I’mafraidnot.)3）當(dāng)你自己是決策者，給第二或第三者以命令、警告、允諾或威脅時(shí)，或頒布法律、規(guī)定時(shí)用shalleg.Youshallgooutatonce.andhealsoshall.6.含情態(tài)動(dòng)詞的反意疑問句1）can't表示推測時(shí)，其附加問句應(yīng)與can't后的動(dòng)詞及時(shí)間狀語的含義相呼應(yīng)Shecan'tbeateacher,isshe?Theycan'thavearrivedyesterday,didn'the?2)must表示“必須，有必要”時(shí)，其附加問句用mustn't或needn'tWemuststopforabreaknow,mustn't(needn't)we?Youmustgohomerightnow,needn'tyou?3)當(dāng)mustn't表“禁止”時(shí)，附加疑問句部分用must或mayWemustn'twalkongrass,must(may)we？4）must如果表示推測，附加疑問句部分應(yīng)與must后面的主要?jiǎng)釉~的含義相呼應(yīng)Shemustbeverytired,isn'tshe?Youmusthavesleptverylatelastnight,didn'tyou?YoursistermusthavelearnedEnglishformanyyears,hasn'tshe.5)陳述句中有oughtto時(shí)，附加疑問句部分用oughtn't（英）或shouldn't（美）。Heoughttogettherenow,oughtn't(shouldn't)he?6)陳述句中有usedto時(shí)，附加疑問句部分用usedn't或didn't,后者更常用Youusedtobegoodfriends,usedn'tyou/(didn'tyou)?7)陳述句中有needn't時(shí)，附加疑問句部分用need(must)Heneedn'tgoyet,need(must)he?8)當(dāng)陳述部分有haveto時(shí)，附加疑問句部分常用don't或haven't前者較普遍Wehavetostart,don’tyou/haven’tyou?7．情態(tài)動(dòng)詞應(yīng)注意的問題1）辯異can,beabletocan與beableto僅在表示能力時(shí)意思相同，但can還可表允許和推測。表能力時(shí),can只有現(xiàn)在和過去兩種形式，而beableto則有更多的時(shí)態(tài)形式。表能力時(shí)，作為過去式could在肯定句中與was(were)ableto也有差異，前者不表結(jié)果，而后者說明結(jié)果。must,haveto在含義上的區(qū)別：must僅在表示“必須”時(shí)與haveto同義。但must帶有主觀意志，haveto強(qiáng)調(diào)客觀需要。時(shí)態(tài)上的區(qū)別：must通常只有現(xiàn)在式haveto，而有更多的時(shí)態(tài)形式mustn't,needn'tmustn’t的含義是“禁止”“不應(yīng)該”“不許”。needn’t的含義是“不必”。should,oughttoshould表示一般忠告，指說話人對當(dāng)前的情況作個(gè)人的看法oughtto語氣強(qiáng)帶有一定的針對性，表示從法律或道義的角度考慮某事該不該做。would,usedtowould表示在過去某一段時(shí)間內(nèi)的習(xí)慣動(dòng)作，并未含現(xiàn)在無此習(xí)慣之義。常跟時(shí)間狀語在一起。usedto表示過去持續(xù)的行為或狀態(tài)，現(xiàn)在已不復(fù)存在。usedto,beusedto2)作為情態(tài)動(dòng)詞與行為動(dòng)詞的區(qū)別need作情態(tài)動(dòng)詞“需要”，主要用于否定句和疑問句中。實(shí)義動(dòng)詞，后接帶to不定式，有人稱、數(shù)等變化，可用于不同的句型中。dareA.情態(tài)動(dòng)詞“敢于”，多用于疑問句、否定句條件句。B.實(shí)義動(dòng)詞，后接帶to(可省略)的不定式，有人稱、數(shù)等變化，可用于不同的句型中。eg.Hedidn’tdare(to)dothat.(行為)Hedarednotdothat.（情態(tài)）7．情態(tài)動(dòng)詞的其他用法：1）cannotbut+dosth.“不得不”，“只好”eg.Icannotbutchoosetogo.2）maywell+動(dòng)詞原形“完全能，很可能”=tobeverylikelytoeg.Hemaywellbeproudofhisson.3)mayaswell+動(dòng)詞原形“最好，滿可以，倒不如”=hadbettereg.Wemayaswellstaywhereweare.4)cannot(或never等否定