牛津译林版英语八下Unit8 Grammar (共20张PPT).ppt

1、现在完成时The Chinese government has made laws to prevent all these things in Zhalong.现在完成时构成：have/has+动词过去分词（done)否定:疑问：havent=have not hasnt=has not Ive=I have Hes=He hashave/has donedone:规则与不规则havent/hasnt doneHave/Has+主语+done？Yes,代词+have/has.No,代词+havent/hasnt.肯定:visit_ change_ enjoy_ cry_stop_ plan_

2、mop_visitedenjoyedcriedstoppedplanned规则：moppedchanged上一页 Typeoriginal p.t p.pcostcostcostcomecamecomerunranrunmeetmetmetcatchcaughtcaughtspeakspokespokenforgetforgotforgottendrinkdrankdrunkeatateeatenABBAAAABCABA不规则变化见课本(仿照例句看表格造句）Whohave donehavent doneWeclean the roomclean the windowsee a film coo

3、k dinnerTheyShego to Beijingvisit the Great WallI1.We _ the room but we _ the window.2._ you _ the room?Yes,_ _ you _ the window?No,_have cleanedhavent cleanedHave cleanedwe haveHave We haventcleanedfinish her homeworkWatch Beijing OperaThe Present Perfect TenseWe use the simple past tense to talk a

4、bout what happened at a definite time in the past.Past present Eddie was born four years ago.现在完成时1.现在完成时表示从过去持续到现在的动作或状Eddie has lived with Millie since he was bornEddie has lived with Millie for four years.PastPastpresent4 yearspresent自从.以来1.We _(not see)each other for years.2.Tom _(have)a cold si

5、nce Monday.3.I_(live)here since I came here.havent seenhas hadhave lived表示从过去持续到现在的动作或状态时间状语：for,since自.以来for与since的区别_two years_two years ago_two oclock_I came here_a long time 总结含义一的用法forsincesincesincefor（how long提问）for+时间段since+过去的时间点（since是介词）since+从句（过）（since是连词）2.表示过去已完成,并对现在有一定影响的动作。（区别过去时的含

6、义）(1)Eddie has just eaten Hobos food.Now Hobo has nothing to eat.(2)Who has cleaned the room?How clean it is!时间状语：already(已经），yet(还），just(刚刚），never(从未），ever(曾经），recent（最近的），recently（近来）,before以前already用于现在完成时的肯定句(句中have already done或句末）yet用于现在完成时的否定句或疑问句（句末）用already与yet 填空：She has _seen the film.=Th

7、ey havent finished the work_.Have you read the book _?My mother has already had supper.(改成否定句和一般疑问句并作否定回答alreadyyetyet区别：just“刚刚”(现在完成时）just now“刚才”(过去时）I _just _(see)the ruler.I_the ruler just now.haveseensaw-I have never been to the Great Wall.我从未去过长城。副词ever 多用于疑问句中，“曾经”never,表示“从未”如:-Have you eve

8、r been to the Great Wall?你曾经去过长城吗?1.They _ (finish)their homework already.2.My parents _(not come)back yet.3.He _never_(visit)the Great Wall before.4._your father ever _(be)to Beijing?5._you _(see)the film recently?6.Mother _ just _(clean)the house.Please dont come in.have finishedhavent comehasvisi

9、tedHas beenHaveseenhascleaned区别过去时和现在完成时：过去时描述过去发生的事（和现在无关），一般与表示过去的时间状语连用，如yesterday,last week,in 1990等现在完成时表示到说话时为止已经发生或完成的动作，强调造成的结果或对现在产生的影响。1.Look!I_ (buy)a watch.2.I_(buy)a watch last week.3.-_you _your honework?(finish)-Yes.I _it half an hour ago.总结含义二have boughtboughthavefinishedfinished3.我们还用现在完成时来谈论到现在为止动作发生的次数。e.g.I have already read this book many times.They _(practice)this dialogue twice.have practised判断方法：1.结合句意判断。“已经”2.依据一些副词或时间状语判断。现在完成时常和already,ever,just,never,recently,yet等副词，以及since,for引导的时间状语连用。对照书上p12-14,p133哪些要记录？