情态动词can和could的用法.ppt

Unit2GrammarandUsage Modalverbs Lead inWecanbethereontimetomorrow MayIcomein Shallwebeginnow Youmustobeytheschoolrules Learningobjectives 1 Masterbasicusageofmodalverbs can could 2 Finishtherelevantexercises Self studyguidance 1 RefertotheworkbookonP49andfindoutthedefinitionofmodalverbsandconsiderhowmanymodalverbsyouknow 情态动词的定义 情态动词是一种本身有一定的词义 表示说话人的情绪 态度或语气的动词 但不能单独作谓语 只能和其他动词原形构成谓语 Howmanymodalverbsdoyouknow cancouldmaymightshallshouldmustwillwouldoughtto havetodare daren t need needn t usedto modalverbs can could的用法 二 情态动词的语法功能Wecanusemodalverbstotalkabout ability certainty permission obligation makerequests makesuggestions makeoffers giveadvice 能力 义务 责任 确定性 允许 提出请求 提出建议 提供帮忙 提出忠告 Modalverbs generalintroduction 用法一 Ability 能力 LiuXiangcanrunthe110mhurdleracewithin13seconds 1 Nowmanyofus 能 speakEnglishquitewell butafewyearsago we 不能can指现在的能力could表示过去的能力2 Nowmanyofus 能 speakEnglishquitewell butafewyearsago we 不能 can couldn t areableto weren tableto beableto也可表示能力 它的用法 要比can could要正式一些 但不常用 can beableto区别 Edisonalwayswonderedwhyhenscouldhatch 孵 chickenswhilehewasnotableto Question Arethetwomodalverbsinterchangeable 互换 Ifnot why can表示与生俱来的能力或一种客观可能 而beableto更加强调通过后天的学习和努力获得的能力 或者在某个客观的场合和背景下 能做到的事情 Thefirespreadthroughthehotelveryquicklybuteveryone getout A hadtoB wouldC couldD wasableto D beabletodosth managetodosth succeedindoingsth 3 I msorryI 不能 playtenniswithyourecently 4 It sniceto 能 attendthelecture 5 WangGong 可能能 winthechessgame haven tbeenableto beableto mightbeableto beableto用于不同的时态2 可用在不定式之后3 可用在情态动词之后 Theywill runthismachineontheirowninthreemonths A canB couldC mayD beableto D A 试试吧 用法二 表示允许 permission Can CouldIhavealookatyournewpen Yes youcan No youcan t CouldIborrowyourdictionary Yes ofcourseyou AmightBwillCcanDcould C can could may might Permission允许 informal spoken formal written Can May Could MightIcomein Yes youcan mayYes please No youmustn t Pleasedon t No youmaynot could常用于疑问句中 比can更加委婉 表示礼貌 用于回答时 常用原形can或者may 不可再用过去式could或might 用法三 Makingrequests 提出要求 Canyouhelpmewithmytraining Idon tknowhowtousethisequipment Will Can Could Wouldyouhelpmewithmytraining Yes Iwill can can will will can could would makerequests informal formal 用法四could用于表示的推测 表示可能 1 Wecouldgotherethissummer 对将来的推测 2 Hecouldn thaveenoughmoneyforanewcarnow 对现在的推测 3 Hecouldn tbesinging 对进行的推测 4 Couldhehaveheardthenews 对过去的推测 certainty veryuncertain almostcertain might should may could oughtto will can推测 表示可能 一般只用于否定句和疑问句 而could一般无此限制 1 Wecouldgotherethissummer 肯定句对将来的推测 2 Hecouldn t can thaveenoughmoneyforanewcar 否定句 对现在的推测 3 Hecouldn t can tbesinging 否定句 对进行的推测 4 Could Canhehaveheardthenews 疑问句 对过去的推测 1 How syournewbabysitter 保姆 2011 We askforabetterone Allourkidslovehersomuch A shouldB mightC mustn tD couldn t2 Mary beinParis forIsawherinthetownonlyafewminutesago Amustn tBcan tCshouldn tDmaynotcould推测的语气比can推测的语气较弱can推测的把握性很大 B D can表示理论上或是逻辑上判断的可能性 一般翻译成 会 常用在肯定句中ItisusuallywarminmyhometowninMarch butit berathercoldsometimes AmustBcanCshouldDwould Thatbigcinema seat2 000people canB shouldC oughttoD isableto B A 用法五 can could 1 表示惊异 怀疑 不相信的态度 主要用在否定句 疑问句或惊叹句中 He ssuchanicepersonthathe committhecrime can t 你怎么会如此地粗心 Howcanyoubesocareless Canthisbetrue Why How should can结构表示说话人对某事不能理解 感到意外 惊异 竟会 Whyshouldyoubesolatetoday Howcanyoubesocareless 其他惯用法A can t cannever too can t cannever enough无论怎么 也不为过 越 越好 Youcan tbetoocarefulwhencrossingthestreet B can tbutdosth havenochoicebuttodosth can tchoosebutdosth havetodosth不得不做某事C can thelptodosth can thelpdosth 不能帮忙做某事can twaittodosth 迫不及待做某事can thelpdoingsth 情不自禁做某事can thelpbutdosth 忍不住做某事 can