初中英语中情态动词的基本用法：can,could1.表达“能力”。2.表示“许可”。3.有礼帽地提出“请求”。（用于疑问句）4.谈论“可能性”。5.当主语为事物时可以表示“惊异”。Wecanusethecomputernow,butwecouldn'ttwomonthago.Youcangonow.Couldyoubehereateighto'clocktomorrowmorning?Hecan'tbethemanager,forIsawhimgotoCanadayesterday.Whatonearthcanthismean?在表达“能力”时，可用beableto来取代can。要注意的是：可在beableto前加肋动词或情态动词以表达更多的时态或情态，can或could前则不可。Nooneisabletodoit.(=Noonecandoit.)Weshallbeabletofinishtheworknextweek.Ihaven'tbeenabletofindanyjobs.maymight1.表示“允许”2.请求“许可”（用于疑问句）3.谈论“可能性”Youmaygohomenow.HesaidthatImightdrinksomebeer.MayIwatchTVthisevening?---MayIuseyoupen?---Yes,youmay.Hemay/mightcometomorrow.must1.表达“义务”、“责任”。2.进行“肯定的推断”。3.其否定式mustn't表示“（说话人）禁止……，不准……”；用来代替maynot表示“不许可”。Everybodymustobeytherules.Imustgonow.Thisworkmustbefinishedassoonaspossible.TheChineselanguagemusthavethelargestnumberofspeakers.Youmustn'tlendthebooktoothers.在表示“客观需要”时，用haveto而不用must。另外可在haveto前加肋动词或情态动词以构成更多的形式。must前则不可。Youdon'thavetoworryaboutthat.Hehadtospendhischildhoodinhardwork,helpinghisfatherontheirsmallfarm.Thestudentsoftodaywillhavetohowtousethecomputers.shallshould1.表示“必要性”。2.征求“意见”或“看法”，请求指示。3.主语为二、三人称时，表达说话人强烈的意志和决心，有威胁或震慑听话人的作用。Weshouldbestrictinallourwork.WhereshallIwaitforyou?Shallwestartthemeetingnow?Tellhimthatheshallhavethebooktomorrow.YoushalldoasIsay.Youngpeopleshouldlearnhowtousecomputers.在表示“必要性”时，可用oughtot来代替shall，语气更正式一些。willwould1.表示“必然性”。2.表达“意愿”或“意志”。3.询问对方的意愿或提出请求。（用于疑问句）Fishwilldieoutofwater.Everydayshewouldgetupat6:00andlightthefire.Iwilltellyouallaboutit.We'llhelphimifheasksusto.Iwon'tgohomenow.IpromisedthatIwoulddomybest.Wouldyoulikeanothercupoftea?Willyougowithme?Willyouplease...?
