情態動詞ModalVerbs情態助動詞有十三個：may,might;can,could;will,would;shall,should;must,need,dare,usedto,oughtto.

P5.Ex2Discusstheusageofmodalverbs

can&could(1)(本能，智能，體能，技能)Jimisn’tverygoodatmathsorscience,buthecanspeakEnglishverywell.Ourhistorytestwassolonglastweekthatnoonecouldfinishit.(2)(3)泛指“可能”Amanasoldashecanbeveryforgetful.

abilityability（4）補充推測/猜測

1.否定句

can’t/couldn’tbesb./sth.不可能是can’t/couldn’tbedoing不可能正在做can’t/couldn’thavedone不可能做過某事2.疑問句：

Can/Could……bedoing?有可能……嗎？Can/Could……havedone?區別：

肯定句couldhavedone原本可以做卻沒做(5)can和could的用法

還可以表示請求和允許。如：

Canyoufinishthisworktonight?

Mancannotlivewithoutair.

—Can/Could/MayIgonow?

---Could

Icometoseeyoutomorrow?

---Yes,youcan.（否定可用No,I‘mafraidnot.）

補充注意：was/wereabletodo表示過去成功辦成某事==managedtodo,但是could沒有這個意思。Eg:Hewasabletoescapefromtheprison.2.may&might(1)Whatawarddidyougetforthesportscompetition?MayIhavealook?(2)Ourfootballteamdidn’tplayverywelltoday,butwemightdobettertomorrow.permissionorrequestpossibility2）may和might的用法

1.表示許可。

表示請求、允許時，might比may的語氣更委婉如：

Youmaydrivethecar.

—Might/MayIuseyourpen?

—No,youmustn't.

用MayI...征詢對方許可,比較正式，比較客氣。在日常口語中，CanI...更為常見。2.表示推測、可能（疑問句不能用于此意）。

Hemaybeverybusynow.

補充：肯定句：may/mightdo/be可能是/做某事may/mightbedoing可能正在做may/mighthavedone可能已經做3.用于祈使句中表示祝愿。如：

Mayyousucceed!

3.must&can’tWhenyoueatfishyoumustbecarefulwiththebones.WangFenghaswontheEnglishcompetitionthreetimes.Hemustbeverysmart.AmanlandedonMars?Youmustbejoking.Thatcan’tbetrue.adviceornecessityguessingguessing

1.表示必須、必要。(主觀意志)如：

Youmustcomeintime.

—Mustwehandinourexercisebookstoday?

—Yes,youmust.(No,youneedn’t/No,youdon’thaveto./No,youcan’t.)

（2）補充推測/猜測肯定句：mustbesb./sth.一定是mustbedong一定正在做musthavedone一定已經做musthavebeendoing當時一定正在做

2.表示推測、可能（疑問句不能用于此意）。

Hemaybeverybusynow.

補充：肯定句：may/mightdo/be可能是/做某事may/mightbedoing可能正在做may/mighthavedone可能已經做（4）補充推測/猜測

1.否定句can’t/couldn’tbesb./sth.不可能是can’t/couldn’tbedoing不可能正在做can’t/couldn’thavedone不可能做過某事2.疑問句：Can/Could……bedoing?有可能……嗎？Can/Could……havedone?區別：肯定句couldhavedone原本可以做卻沒做haveto的含義與must相似，兩者往往可以互換使用。但有幾點不同：

①must表示的是說話人的主觀看法，而haveto則往往強調客觀需要。如：

Theplayisnotinteresting.Ireallymustgonow.

IhadtoworkwhenIwasyourage.

②must一般只表現在，have則有更多的時態形式。

③二者的否定意義不大相同。如：

Youmustn‘tgo.你可不要去。

Youdon’thavetogo.你不必去。④詢問對方的意愿時應用must。如：

MustIcleanalltheroom?4shall和should的用法

1.shall用于一和三人稱疑問句中，表示說話人征求對方的意見或向對方請示。如：

Shallwebeginourlesson?

Whenshallhebeabletoleavethehospital?2.Shall用于二和三人稱肯定句中，表示許諾、命令、警告，威脅Youshallgetmyanswertomorrow.Heshallbepunishedforwhathehasdone.3.Should除了表“應該”，還表推測。“照說應該、估計”4.shall&shouldTheharvestfestivalbeginsonSaturday.Weshallbetherewithourfriends.Whengoingbyplane,youshouldarriveattheairportatleastonehourearly.It’snearlytimeforclasstostart.Theteachershouldbeheresoon.promisepredictionprediction補充oughtto與should同，否定式為oughtnotto5.will&wouldDuringtheSpringFestivaltimethewholefamilywillcomefordinner.Myunclewaspoorbutlikedfashion,sohewouldoftendressupasarichman.AreyoufreethisSaturday?Wouldyouliketojoinmyfamilyfordinner?promiseorpredictionpasthabitrequest3）will和would的用法

1.表示意志、愿望和決心。如：

Iwillneverdothatagain.

Theyaskedifwewoulddothatagain.2.表示請求、建議等，would比will委婉客氣。如：Would/Willyoupassmethebook?3.would可表示①過去反復發生的動作或某種傾向,②不與表心理或狀態的詞連用，③現在是否結束不清楚usedto既①可以表示過去經常的動作，也可以示狀態，

②暗含現在已不沒有這樣了。如：

I________likeice-cream.Afterherson’sdeath,she_______sitbythewindow,deepinthought.usedtowould補充needdo/neednotdo情態動詞，無人稱時態變化，多用于疑問和否定句中needtodo/……notneedtodo實意動詞，有人稱時態變化，多用于肯定句和否定句中。Exercises1.Jane______________(keep)herword,Iwonderwhyshechangedhermind.2.Iwasonthehighwaywhenthiscarwentpassfollowedbyapolicecar.They____________________(drive)atleast150kilometresanhour.IfI____________(plan)todoanythingIwantedto,I’dliketogotoTibetandtravelthroughasmuchofitaspossible.shouldhavekeptmusthavebeendrivingcouldplanMissFang__1__(not)readforverylongwithoutgettingaheadache.Hermothertoldherthatshe__2__gototheHealthServiceandseeadoctor.“You__3___seeadoctorassoonaspossible,”shesaid,“You__4__needglasses.”WhenMissFanghadfreetime,shewenttotheHealthService.Theappointmentclerksaidthatthedoctor__5___seeherat3:30.MissFangrepliedthatshe__6__notbeabletobethereat3:30becauseshehadaclassthen.”Thedoctor__7__takeyouatabouttentofour,”theappointmentclerksuggested.“___8__Iputyoudownfortentofour,or___9___yourathercometomorrow?”MissFangthoughshe__10___(not)wasteanymoretime.Theteacher__11___beunhappyifsheaskedforpermissiontoleavetheclassalittleearly,ashewasalwayssokindtoeveryone.Andshereplied,“IthinkI__12___makeitattentofour.”MissFangwenttotheclass.Sheaskedherteacher,“__13___Ileaveat3”45today?I__14__haveaneyeexamination.”Asexpected,theteachersaid,“Yes,ofcourseyou__15___.”MissFang1_________(not)readforverylongwithoutgettingaheadache.Hermothertoldherthatshe2________gototheHealthServiceandseeadoctor.“You3_______seeadoctorassoonaspossible,”shesaid,“You4_______needglasses.”WhenMissFanghadfreetime,shewenttotheHealthService.Theappointmentclerksaidthatthedoctor5_______seeherat3:30.MissFangrepliedthatshe6_______notbeabletobethereat3:30becauseshehadaclassthen.”Thedoctor7_________takecouldn’tshouldshouldmightcouldwouldmightyouatabouttentofour,”theappointmentclerksuggested.“8_____Iputyoudownfortentofour,or9______yourathercometomorrow?”MissFangthoughtshe10__________(not)wasteanymoretime.Theteacher11_________(not)beunhappyifsheaskedforpermissiontoleavetheclassalittleearly,ashewasalwayssokindtoeveryone.Andshereplied,“IthinkI12______makeitattentofour.”MissFangwenttotheclass.Sheaskedherteacher,“13_________Ileaveat3”45today?I14_____haveaneyeexamination.”Asexpected,theteachersaid,“Yes,ofcourseyou15_______.”Shallwouldshouldn’tshouldn’tcanCan/Maymustcan虛擬語氣1）虛擬語氣用于下列表示“命令要求建議勸告”等意義的動詞的賓語從句，由（should）+動詞原形構成。一堅持insist(堅持要求)二命令order,command三建議advise,suggest（建議）,propose四要求demand,require,request,ask，desire1.Sheinsisted(that)she____________(notsteal)thebook.2.Sheinsisted(that)he____________(tell)thetruth.3.Shesuggested(that)I______(look)unwell.4.Shesuggested(that)I________(see)adoctorassoonaspossible.1.wish+從句（虛擬語氣）表示對現在的愿望虛擬時用過去式或情態動詞過去式+do表示對將來的愿望虛擬時用情態動詞過去式+do表示對過去的愿望虛擬時用had+p.p或could/would/might+have+p.pIwishIwere

asinger/Icouldfly.IwishIwouldbeamillionaireoneday.Theplaywasbad,IwishIhadnotgonetothetheatre.2.wouldrather+從句(虛擬語氣)

“寧愿……”表示對現在或將來的愿望虛擬時用過去式表示對過去的愿望虛擬時用had+p.pIwouldratheryouhadn’tcomeyesterday.Iwouldratherthemid-termexamcameearlier.3.Ifonly…(要是…就好了)

之后的虛擬語氣表示對現在或將來的愿望虛擬時用過去式或情態動詞過去式+do表示對過去的愿望虛擬時用had+p.pIfonlyIhadworkedharder.IfonlyIcouldchangetheworld.4.asif/though+從句虛擬語氣

陳述語氣表示對現在或將來的愿望虛擬時用過去式或情態動詞過去式+do表示對過去的愿望虛擬時用had+p.pThestickinaglassofwaterlooksasifitwerebroken.Heateasifhehadn’thadmealsforthreedays.Itlooksasifitisgoingtorain.5.Itis(high/about)timethat…句型

（做）…的時間到了在此句型中，從句要用過去式表虛擬It’shightimewemadeallourefforts.=It’shightimeforustomakeallourefforts.

其它使用虛擬語氣的情況見名師面對面

第二節中的第3和第4點三.IFSentenceStructure‘IF’虛擬條件句的結構IF虛擬條件句根據條件所處時態分為三類.

a.表示與現在事實相反

的假設.

b.表示與過去事實相反

的假設.

c.表示與將來事實相反

的假設.translation1.IfIwereyou,Iwouldtrymybesttogetthechance.=WereIyou,……2.IfIhadworkedharder,Iwouldn’thavefailedintheexam.=HadIworked,……3.I fIhadeatenmore,Iwouldn’tbehungrynow.=HadIeatenmore,……區別2與3的后半句4.Howwonderfulitwouldbeifitsnowed/shouldsnow/weretosnowtomorrow!=Howwonderfulitwouldbeshoulditsnow!=Howwonderfulitwouldbewereittosnow！Conclusion:if假設從句中若有助動詞had,were或should,可以去掉if，提前助動詞had,were或sh