英语现在完成时

英语现在完成时一．基本结构have(has)+been+done(动词的现在分词)否定句式have(has)+not+been+done(动词的现在分词)疑问句式have（has）放在句首二．用法1.过去发生的动作对现在有影响Ihaveseenthefilm,soIknowwhatthestorysays.2.过去发生的动作持续到现在（还有可能继续发生）Thefilmhasbeenonfor5minutes.三．延续性动词1.现在完成时中应使用延续性动词2.非延续性动词：动作开始既（即）结束3.非延续性动词过渡到延续性动词常见:四．标志1.already,yet,never,ever,just,before,once/twice/数字+times(1)already,yetalready:用于肯定句，疑问句中，表示“已经”或表示强调Hehasalreadylefthere.Hashealreadylefthere.yet：用于否定句中，疑问句中，表示“还没”或“已经”Myteacherhasn’thadbreakfastyet.Haveyouwrittentoyourparentsyet?(2)never,evernever:从来没有ever：曾经WehaveneverbeentotheGreatwall.HaveyoueverbeentoCanada?(3)just刚才Iamjusthadbreakfast.2.allthetime总是,duringthelastyears在过去的几年里recently最近地=lately,bytheendof(thismonth,nextyear)inthepastfewyears/month在过去的……间uptonow直到现在3.for+段时间，since+点时间Ihavebeenherefor5years.Ihavebeenheresince2000.Ihavebeenheresince5yearsago.since+段时间+agoIhavebeenheresinceIgraduatedin2000.since+从句have/hasgoneto去了没回来have/hasbeento去了回来了have/hasbeenin在某地待多久for+段时间，since+点时间用howlong提问四．固定句型1．Since句型。“since+一般过去时”Since从句中用非延续性动词或终止性动词表示肯定Since从句中用延续性动词表示否定IthasonlybeenfourdayssinceyouwenttoTokyo,butitseemslikeit’sbeenfouryears.Ithas/isbeen5yearssincehebegantosmoke.2.this/it+was/is+（oneof）themost/best+形容词最高级+n.(pl.)+that+完成时ThisisthemostinterestingbookthatIhaveeverread.3.this/it+was/is+thefirst/second/其他序数词/last+time+that+现在完成时/过去完成时ThisisthefirsttimechildrenhavetakenpartinGeneralAssemblyactivitiesinsuchsizeandnumber.