情态动词讲义高三英语下学期二轮复习专项

高中语法精讲九<情态动词>基本语法规则：①无人称和数的变化②+V原,构成谓语动词dare和need特殊用法：dare作实义动词放肯定句，daretodosth（有人称/数的变化）放否/疑句，dare（to）dosth（有人称/数的变化）dare作情态动词放否定句/疑问句/条件句need作实义动词主动：needtodo（有人称/数的变化）被动：needdoing（有人称/数的变化）needtobedone（有人称/数的变化）need作情态动词放否定句/疑问句/条件句情态动词短语用法：肯定式hadbetterdosthusedtodosthoughttodosth否定式hadbetternotdosthusednottodosth=didn’tusetodooughtnottodosth疑问式Hadsb.betterdosthUsedsb.nottodosth=DidsbusetodosthOughtsb.todosth情态动词表达推测：推测现在/将来：①can/may表“可能”②can't表“不可能”③must表“肯定”might/could可能性<can/may可能性can’t<couldn’t<maynot<might<may<oughtto<could<must（可能性排列顺序）can：理论推测，放否/疑句may：事实预测，放肯定句could：对过去推测：放肯/否/疑句should：非常可能的推测推测过去：情态动词+have+donemusthavedone....can’t/couldn’thavedone.....过去一定做了....不可能已经做了....shouldhavedone....could/may/mighthavedone.....本应该做.....或许已经做....（可能性could>may>might）含有情态动词推测的反义疑问句：按照原来句子时态情况变化Eg.Hemustbeathome,isn’the?Eg.Hemusthavegoneabroad，hasn'the?Eg.Hemusthavelosthisbookyesterday，didn'the?情态动词中虚拟语气用法：{必须过去式，如could/mighthavedone}couldhavedone本可以做..../couldn’thavedone本不可以做...mighthavedone本有可能做..../mightn’thavedone本不可能做...shouldhavedone本应该做..../shouldn’thavedone本不应该做...needn'thavedone本不必做.....was/weretohavedone本打算做.....wouldliketohavedone本想要做.....wouldratherhavedone本希望做.....Hadwanted/planned/meant/hoped/intended+to+do=wanted/planned/meant/hoped/intendedtohavedone.....情态动词can其他用法：①表能够=beableto(有时态，成功做成)②表惊讶（否/疑/感叹句）Eg.Howcanyoubesorude?③can't....too/enough....:怎样也不算过分Eg.Youcan’tbetoocarefulwhilecrossingthebusystreet.④can'thelpdoingsth.=can'thelpbutdosth.=can'tbutdosth.“情不自禁做某事”情态动词may其他用法：MayI...？请求别人，对自己有利ShallI...？征求意见，对他人有利May+第一/二人称，表祝福may/mightaswell“最好/倒不如”=hadbetterEg.Youmightaswellstayinbedtohaveagoodrest.maywell“很可能”：Shemaywellnotwanttolivealone.情态动词shall具体用法：表承诺/法律/规章/义务等：“必须”用于第一人称，陈述将要发生的事情Eg.Ishallgotothecitytomorrow.用于第二/三人称陈述句中，表决心/命令/允诺/威胁/主观意志用于第一/三人称陈述句中，表征求意见情态动词should具体用法：（shall的过去式，表建议/劝告）表现在情况表示吃惊，“竟然”→对过去情况吃惊:shouldhavedone句型：Itissurprising/strange/apitythatyoushouldbesofoolish.②表“万一”情态动词will具体用法：will+第一人称，表决心/允诺/威胁/意志：Eg.I’llkillyousoonerorlater.will+第一人称，陈述将要发生的事情If条件句中，will表意愿，并非表将来；若要表将来，则beto...表现在的一种倾向和习惯非人称主语+won't，表示某物暂时的特性，“不能....”Eg.Thewindowwon’topennow.情态动词would具体用法：表过去某种习惯，倾向，“总是”过去的意志/意图，“愿意”非人称主语+wouldn't，表示某物暂时的特性，“不能....”注意：Don'tgothere;itistoodangerous!No,Iwon’t.(前面否定，No就是Yes，和反义疑问句的理解一样)14.情态动词must用法：（must的过去式must）①“偏要”，语气不耐烦表自然规律，必然结果：Allmanmustdie.mustn't：“千万不要高中语法精讲十<虚拟语气>wish和hope对比：wish用法hope用法+宾语从句（虚拟语气）+宾语从句（陈述语气）+不定式+不定式+复合宾语/双宾：Iwishyouagoodfuture.ifonly和onlyif对比：ifonly用法onlyif用法翻译：“如果....就好了”翻译：“只要”①对现在情况虚拟，用过去时②对过去情况虚拟，用过去完成时Itisabout/hightimethat从句（过去式/should+V原）should不省略“早该做....了”should不省略wouldrather=’drather“宁愿”表示现在/将来的愿望，从句+过去时例：I’dratheryoucametomorrow.表示与过去相反的愿望，从句+过完例：I’dratheryouhadfinishedit.真实条件句（假设的情况可能发生）虚拟条件句（对过去/现在/将来假设，情况相反）陈述语气虚拟语气普通虚拟条件句的理解：具体展开如下：时间从句（V）情况主句（V）情况与现在相反过去时wouldwould/should/could/mightdo与将来相反①过去时②shoulddo③weretodo与过去相反过去完成时would/should/could/mighthavedone例1:Ifitweren’trainingsohard,wewouldgotothebeach.例2：sankSupposingthisshipweretosink,whatwouldwedotosaveourselves?shouldsink例3：Ifthenowlawhadbeenputintouse,theaccidentwouldn’thavehappened.错综虚拟条件句的理解：主从句时间不一致，具体情况具体分析从过去，主将来（错综虚拟语气）Iftheyhadstartedintheearlymorning,theywouldarriveinhalfanhour.从过去，主现在（错综虚拟语气）Iftheyhadstartedintheearlymorning,theywouldbetherenow.从过去，主过去（普通虚拟语气）Iftheyhadstartedintheearlymorning,theywouldhavearrived.If引导的虚拟语气用法：If引导的虚拟条件句中有were/had/should,则省略if,把were/had/should提到sb前面，用倒装结构。例1：Ifitshouldraintomorrow，weshouldhavetoputoffourplan.Shoulditraintomorrow，weshouldhavetoputoffourplan.例2：IfIhadcatchthefirstbus,Iwouldnothavebeenlateforschool.HadIcatchthefirstbus,Iwouldnothavebeenlateforschool.条件分句的理解:真实条件句非真实条件句零条件句第一条件句第二条件句第三条件句客观事实/科学理论可能会发生的假设/条件与现在事实相反/将来不可能实现的条件与过去事实相反的条件/假设主现从现主将从现主虚拟从过完✦✦注意✦✦注意：在虚拟语气中，用were；倒装虚拟和ifIwereyou中，也只用were.Eg.IfIwereyou,Iwouldstudyharder.含蓄条件句的理解：（部分句子省略了表示虚拟语气的的词，短语）表示虚拟语气的词/短语：otherwise/inthatcase/with/without/butfor/or/but/evenif/eventhough/asthough/asif/.例1：Withoutwaterwecouldnotliveontheearth.例2：Butforthestormwewouldhavebeenthereinviding/provided“倘若“；作连词，引导条件状语从句，不用虚拟语气。supposing/suppose”如果，假设”；引导条件状语从句，用虚拟语气或陈述语气。句型1:Ifitweren’tfor.....如果不是....(与现在相反)句型2:Ifithadn’tbeenfor.....如果不是....(与过去相反)注意：一个句子可以虚拟语气和陈述一起，具体辨别：陈述说的是事实；虚拟语气说的是假设，体现条件从句和主句的谓语动词。（should）+V原的虚拟语气：表建议/要求常用（should）+V原的动词Insist坚持要求ordersuggest建议demandmandurgeproposeremendrequestrequirepreferaskadvise...............Eg.Myfather