Unit 5 Educational exchanges现在完成时课件英语八年级上册.pptx

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1、,现在完成时的表达,05-现在完成时与非延续性动词,06-现在完成时一般过去时的区别,04-现在完成时的三个特殊句式,01-现在完成时的定义,02-现在完成时的结构,03-现在完成时的时间标志词,现在完成时(the Present Perfect Tense)定义：,时态定义：A表示过去发生或已经完成的动作对现在造成的影响或结果，强调对现在造成的影想或结果）。例如： The car has arrived.车子来了。（结果：车子已在门口）Someone has broken the window.有人把窗户打破了。（结果：窗户仍破着）,现在完成时(the Present Perfect Ten

2、se)定义：,B. 表示过去已经开始，持续到现在的动作或状态，可以和表示从过去某一时刻延续到现在（包括“现在”在内）的一段时间的状语连用,如for+时间段、since+过去的时间点、疑问词how long等。例如：My uncle has worked at this factory for five years.我叔叔在这个工厂工作已经五年了。Mr. Black has lived in China since 2002.自从2002年Mr. Black 一直住在中国。How long have you been here? 你来这里多久了？注意：此种用法中表示持续动作或状态的动词必须是延续

3、性动词。,现在完成时的结构：,主语+have/has （助动词）+动词的过去分词,肯定句：主语+have/has+动词的过去分词+宾语.否定句：主语+have/has+not+动词的过去分词+宾语.一般疑问句：Have/Has+主语+动词的过去分词+宾语.特殊疑问句：特殊疑问词或词组+一般疑问句（have/has+主语+过去分词（V-ed）+其他),过去分词变化规则：,规则变化： 1.一般情况 直接加-ed wantwanted playplayed2.以e结尾的动词 直接加-d hopehoped livelived3.以元辅字母构成的重读闭音节结尾的动词，先双写这个辅音字母，再加-ed s

4、top stopped shopshoppedplanplanned4.以辅音字母加y结尾的 变y为i，再加-ed studystudied worryworried,过去分词变化规则：,不规则变化： (2)不规则动词变化需参看不规则动词表逐一熟记。A-A-A型 A-A-B型 A-B-B型A-B-A型 A-B-C型例如：cutcutcut beginbeganbegun thinkthoughtthought runranrun,现在完成时用法以及时间标志：,（1）表示发生在过去的动作或已经完成的动作对现在造成的影响或者结果，常用的状语有already,yet,not. yet,now,jus

5、t by this time等e.g.The bus has come here. 公共汽车已经来了。(对现在的影响是乘客可以上车了)e.g.Someone has cleaned the window. 有人已经擦了窗户。（对现在的影响是窗户现在是干净的）（2）表示过去已经开始，持续到现在而且可能继续下去的动作，常常与for+时间段或since+时间点连用。e.g.We have been here for two years 我们在这里两年了。e.g.I havent heard from her since last year 我自从去年就没有收到她的来信了。,现在完成时的三个特殊句式:

6、, have been (to): 曾经去过或到过（某地）（表示某人过去的经历） have gone (to)：去（某地）了（现在可能在途中或已经到达某地） have been in. + 一段时间: 已待在某地一段时间了,He has been to Hangzhou many times.他到过杭州很多次了。He has gone to Hangzhou,so he cant help us.他去杭州了，所以他不可能帮助我们。She has been in London for half a year.她在伦敦已经半年了。,现在完成时与非延续性动词：,（1） buy,borrow,die等

7、非延续性动词（也称为瞬间动词）的肯定形式一般不能和表示一段时间的for短语及since短语（或从句）连用，这时要用相应的动词代替这些非延续性动词。e.g.I have bought the bike for two years. () I have had the bike for two years. () 我已经买了这辆自行车两年了。 由于buy是瞬间动词，无法延续两年，所以改为延续性动词had。,(2)非延续性动词与一段时间状语（for+一段时间、since）连用时可采用将非延续性动词转化为延续性动词的方式。瞬间动词与延续动词的转换：,【注意】非延续性动词在现在完成时当中，不与for+一

8、段时间以及since+时间点连用的时候不需要换成延续性动词e.g. He has left here. 他已经离开了这里。e.g. He has been away from here for two years. 他已经离开这里两年了。,现在完成时与一般过去时区别,1.侧重点不同现在完成时和一般过去时相同点为表示的动作都发生在过去，但它们所强调的重点不同：现在完成时侧重于对现在的影响；而一般过去时侧重于某一动作发生在过去某个时间或某段时间，即现在完成时侧重于现在的结果，而一般过去时侧重于动作发生的时间。 e.g.I have seen the film. 我看过这部电影。（现在我仍记得电影的

9、内容） I saw the film three days ago. 三天前我看了这部电影。（强调是三天前，而不是别的什么时候看的电影）,现在完成时与一般过去时区别,2.时间状语不同 现在完成时：for,since,so far,ever,never,just,already,yet,since.ago,in the past/last few years等不确定的时间状语.一般过去时：yesterday,once(曾经)just now,last week/month., .ago,in the past 等具体的过去时间状。,综合训练：,用for 或since填空：1.Ive taken

10、driving lessons _last month.2.My sister has had her cell phone _a month. 3.My friends havent visited me _ few days ago.3.Tom has worn glasses _ he was 7 years old.4.Its five years _(for/since) we met last time.,综合训练：,用动词的适当形式填空（注意时态）1. -_ you _your pen? (mend) -Yes, I _. -When_ you _ it? -I _ it yes

11、terday.2. -How do you like the film? -I _(not see) such a moving film before. 3.Millies sister _(join) the club last week. So she _(be) in the club for nearly one week.3.Millies sister _(join) the club last week. So she _(be) in the club for nearly one week.,综合训练：,1. Look! That man looks like Mr. Br

12、own. It be him, for he America. A. cant；has gone to B. may not；has gone C. may not；has gone D. may not；has gone,综合训练：,2. Diana cant go to the farm with her classmates because shea bad cold. A. will catch B. is catching C. will catch D. is caught,综合训练：,3. Mary, along with her parents, Hainan for a we

13、ek and they will come back soon. A. have been to B. has been in C. have been in D. has been to,综合训练：,4. Mr Jiang the company to develop the 5G network for years. Now he works as the chief engineer in it. A. joined B. was a member of C. has joined D. has been a member of,综合训练：,5. Sorry, Im late. Has

14、the meeting begun?It doesnt matter. The meeting for several minutes. A. has just begun B. has just been over C. has just been on D. has just ended,综合训练：,6. Sorry, Im late. Has the meeting begun?It doesnt matter. The meeting for several minutes. A. has just begun B. has just been over C. has just bee

15、n on D. has just ended,综合训练：,7. My friends new restaurant in Wanda Plaza（ 万达广场 ） two years ago, but I there so far. A. has opened; havent been B. was open; havent been C. opened; havent gone D. has been open; havent gone,综合训练：,8. How long did you stay in Hainan during the summer holiday?I there for

16、one week. I have never had such a happy holiday. A. have stayed B. stayed C. will stay D. has stayed,综合训练：,9. It ten years many changes in the town. A. is; since; have taken place B. is; since; have taken place C. was; since; have happened D. has been; since; took place,综合训练：,10. you ever for a newspaper? Yes, I have. I think its a good experience for me. A. Do; write B. Did; write C. Have; written D. Will; write,谢谢观看,