学牛津版必修二Unit 1 Tales of the unexplainedgrammar课件（共17张PPT）.ppt

m2u1grammarandusage presentperfecttense presentperfectcontinuoustense revision translatethefollowingsentences 美国警方现已加紧对一名15岁男孩的搜索 peopleinamericahavesteppeduptheirsearchforafifteen year oldboy 自从上周五晚我就没有看到贾斯汀了 ihavenotseenjustinsincelastfridaynight 该事件引起了公众的极大兴趣 thisincidenthasreceivedgreatinterest presentperfecttense presentperfecttense现在完成时 结构 has have doneweusethepresentperfecttensewhentheexacttimeofanactionisnotclearorimportant weuseitwithtimeexpressionssuchas already 肯定 yet 否定 just lately recently never ever for 一段时间 since 时间点 presentperfecttense现在完成时 动作完成 1 weusepresentperfecttensetotalkaboutthingsthathappenedintherecentpastbutareconnectedwiththepresent 主要为短暂性动词 justinhasdisappeared sokellyisverysad practice she lose herbike she lose herbikeyesterday she have agoodeducation she have agoodeducationwhenshewasyoung presentperfecttense现在完成时 动作未完成 2 wealsousethepresentperfecttensetotalkaboutsomethingthatstartedinthepastandisstillhappeningnow 延续性动词或表状态的形容词 ihavenotseenjustinsincelastfridaynight 常与since sofar for bynow untilnow recently等连用 瞬间性动词如arrive join die get come buy sell leave borrow marry等 以及终止性动词如start begin finish等 在现在完成时的肯定形式中不能与 for 一段时间 的时间状语连用 但可以用在否定句或这些动词对应的状态动词中 为了表述这种意思 我们常用相应的延续性动词have keep be 等来代替非延续性动词 ihaveseenhimforamonth ihaven tseenhimforamonth 错 对 practice 1 theprice recently butidoubtwhetheritwillremainso awentdown bwillgodownchasgonedowndwasgoingdown2 inthepastfewyearsthere greatchangesindamiaotown aisbwerechavebeendwillbe presentperfecttense现在完成时 3 weusethepresentperfecttenseforrepeatedactions 常与频度副词always often never seldom等连用 somewillagessaythattheyhaveseenufosmanytimes practice it rain everydaythisweek she always walk toschool i never see suchabeautifulbird i go be tothegreatwalltwice 现在完成时的几点补充 1 havebeen to 与havegone to 的区别havebeen to 表示 去过某地现在已经回来了 havegone to 表示 去某地了还没有回来 前者可与once never severaltimes等连用 后者不能 hehasgonetohangzhou hehasbeentohangzhoutwice hehasneverbeentohangzhou hehasoncebeentohangzhou 现在完成时的几点补充 2 在时间 条件状语从句中 常用现在完成时代替将来完成时 don tgetoffthebusuntilithasstopped unlessyouhavefinishedyourhomework iwon tallowyoutowatchtv presentperfectcontinuoustense现在完成进行时 结构 has havebeendoing1 weusethepresentperfectcontinuoustensetotalkaboutactionsthatstartedinthepastandarestillcontinuing ihavenotbeensleepingwellsinceireturnedhome 现在完成进行时 2 wealsousethepresentperfectcontinuoustensetotalkaboutactionsthathavejustfinishedbutarestillconnectedwiththepresentinsomeway kelly sorry i mlate haveyoubeenwaitinglong mavis yes ihavebeenwaitingforanhour nowthatsheisoutofajob lucy goingbacktoschool butshehasn tdecidedyet a hadconsideredb hasbeenconsideringc consideredd isgoingtoconsider practice 2 wherehaveyoubeen we foryoueverywhere a lookb werelookingc hav