Unit 8 Have you read Treasure Island yet? 语法专项课件

(共20张PPT)
Unit8
语法专项课件
（现在完成时1）
初中英语人教版八年级下册
现在完成时结构
肯定句：主语 + have/ has + 过去分词+...
否定句:主语+haven’t ( have not) +过去分词… 主语+hasn’t ( has not ) +过去分词...
疑问句:Have / Has+主语+过去分词...
I haven’t finished my homework.
Have you finished your homework
I have finished my homework.
结构
现在完成时三大用法
用法1
1) 表示到现在为止已经完成或刚刚完成的动作。
By now, I have collected all the data I need.
Now we have planted all the trees.
现在完成时三大用法
用法2
2) 表示过去发生的动作,强调结果或对现在的影响。
Someone has broken the window.
I have just cleaned my hands.
(窗户现在是坏的)
(手是干净的)
现在完成时三大用法
用法3
3) 表示从过去开始并持续到现在的动作或状态。
She has learned English for 5 years.
He has lived in Beijing since he was born .
过去式、过去分词
(1)一般动词，在词尾直接加“ ed ”。
work---worked---worked
(2)以“ e ”结尾的动词，只在词尾加“ d ”。
　 live---lived---lived
(3)以“辅音字母 + y ”结尾的动词，将“y” 变为 “i”，再加“ ed ”。
study---studied---studied
(4)重读闭音节结尾，末尾只有一个辅音字母，先 双写该辅音字母，再加“ ed ”。
drop---dropped--dropped
规则变化
过去式、过去分词
不规则变化
A.过去分词与过去式形式一样
have—had—had spend —spent—spent
make—made—made say—said—said
find—found—found hear—heard—heard
meet—met—met leave—left—left
过去式、过去分词
不规则变化
B.过去分词与过去式形式不一样
take—took—taken
speak —spoke—spoken
sing—sang—sung
drive—drove—driven
be—was/were—been
go—went—gone
过去式、过去分词
不规则变化
C.过去分词、过去式与动词原形一样
cut—cut—cut
put —put—put
let—let—let
read—read—read
易错点
2012
started learning English
2015
learning
3 years
have learned English
I started learning English in 2012.
I am learning English these days.
I have learned English for 3 years.
（一般过去时）
（现在进行时）
（现在完成时）
现在完成时VS一般过去时
易错点
现在完成时/一般过去时用法不同
现在完成时 一般过去时
用法1：表示到现在为止已经完成的动作。 用法1：表示过去某时发生的动作。
用法2：表示动作发生在过去，对现在造成影响。 用法2：表示过去存在的某种状态。
用法3：表示动作开始于过去，一直持续到现在，并有可能继续持续下去。 用法3：表示过去经常性发生的动作或状态。
易错点
现在完成时/一般过去时用法不同
I saw this film yesterday.
I have seen this film.
（一般过去时：强调动作）
（现在完成时：强调影响）
已经知道内容
易错点
现在完成时/一般过去时结构不同
现在完成时 一般过去时
肯定句： 主语 + have/ has + 过去分词 +... 肯定句：主语 + 过去式 +...
主语 + was/were + 表语.
否定句: 主语+haven’t ( have not) +过去分词+... 主语+hasn’t ( has not ) +过去分词+... 否定句：
主语 + did not (didn’t) + 动词原形 + …
…was/were not （wasn’t/weren’t) + 表语.
疑问句:Have / Has+主语+过去分词... 疑问句：Did + 主语 + 动词原形 + …
Was/Were + 主语 + 表语
易错点
现在完成时经典例句：
I have been to Australia before.
I haven’t been to Australia before.
Have you been to Australia before
现在完成时/一般过去时结构不同
易错点
现在完成时/一般过去时结构不同
一般过去时经典例句：
My father flew to Australia yesterday.
My father didn’t fly to Australia yesterday.
Did you father fly to Australia yesterday
易错点
现在完成时/一般过去时标志词不同
现在完成时 一般过去时
副词作标志词：just, already, yet 过去时间点：just now, at that time, yesterday, this morning, three years ago
since + 时间点/(时间段+ago)/一般过去时句子 for + 时间段 过去时间段：in the past, in + 过去的年份, last week, once upon a time等
表示次数的时间状语：once, twice, three times, ever, never 特殊结构：
used to + 动词原形 （过去常常）
易错点
现在完成时/一般过去时标志词不同
She returned yesterday.
There was a temple in the past.
He has been in New York for many years.
Have you ever been to Beijing？
（一般过去时）
（现在完成时）
【典例1】He _______ in this factory for 20 years already.
A. will work B. works
C. has worked D. is working
考查时态。already为现在完成时标志词,且 for + 时间段表明对现在的“影响”，故选用现在完成时结构have/has done。
【典例2】—Is Richard still living here
—No, he ______ to Paris already.
A. had moved B. moved
C. will move D. has moved
考查时态。No说明Richard不在此处，且already为完成时标志词，选用现在完成时结构have/has done。
【典例3】Julie’s father ______ to London last month. He ______ there three times.
A. went, had gone B. has gone, has been
C. went, has been D. has been, had gone
考查时态。last month为一般过去时标志词，选用went；three times表明去伦敦的“结果”“影响”，选用现在完成时。