现在完成时态•have/has+过去分词PresentperfecttenseThestructureofthePresentPerfectTenseis:subjectaux
vmainv+Ihaveseenit
+Youhaveeatenmine
_ShehasnotbeentoRome
_Wehavenotplayedfootball
HaveyoufinishedIt
HashedoneIt
通常使用现在完成时的几种情况:•1表示发生在过去对现在仍有影响的动作
•Wehavealreadycleanedtheclassroom
•ThedisappearanceofJustinhasmadeKellyveryunhappy
•Ihavealreadyreadthebook
•Theboyhascomeback
表示一个刚刚完成的动作•TheyhavejustreturnedfromFrance
•3表示过去发生反复多次的动作
•ThecityisveryfamiliartomebecauseIhavevisitedittwice
•Youdon’tneedtodescribeher,forIhavemetherseveraltimes
•ThismonthIhavebeentoBeijingfor5times
常与twice,threetimes等连用4表示过去开始的动作或状态一直延续到现在表示动作只能用于某些带有延续意义的动词
•Shehastaughtheresincetenyearsago
•Since1949,Chinesepeoplehavelivedabetterlife
•Wehavebeeninthisschoolfor3months
•WehavelearnedEnglishfor10years
•瞬间动作要用否定式才能延续•Ihaven’