外研版(2019)选择性必修第一册Unit 5 Revealing nature Using Language过去完成时 课件(18张ppt)

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名称 外研版(2019)选择性必修第一册Unit 5 Revealing nature Using Language过去完成时 课件(18张ppt)
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版本资源 外研版(2019)
科目 英语
更新时间 2022-11-21 21:18:22

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(共18张PPT)
Unit5 Using Language
过去完成时
a. Darwin suspected that the finches had evolved from a common ancestor …
b. Many people refused to believe that living things, including humans, had evolved from lower forms of life.
过去完成时
What does the structure had done indicate
It indicates the action happened
before a certain past action.
present
past
past perfect
time
the action which occurs previously in time is expressed in the past perfect tense
the action which occurs later is expressed in the past tense
过去完成时
过去
现在
过去完成时是很重要的动词的时态,也是大家在使用中常常出错的语法项目。大家应在了解其基本概念和用法的基础之上,深刻理解“过去的过去”的含义,并在活动中加以体会。
【构成】
肯定式为“had +过去分词”
否定式为“had not +过去分词”
思考:had在结构中的功能是什么?
【用法】
1. 表示“过去的过去”,即站在“过去”的角度回顾一个更远的过去。
eg Before we got to the train station, the train had already left.
(我们到达火车站之前,火车就已经离开了。)
助动词
过去完成时
2. 表示从过去某一时间开始,一直延续到过去的另一个时间的动作,常用的时间状语有be then, by the end of, by the time.
eg By the end of last term, we had learnt 2,000 English words.
(到上学期期末为止,我们已经学习了2,000个英语单词了。)
They had lived there for ten years by then.
(到那时为止,他们已经在那里住了10年了。)
3. 表示愿望、打算等的动词,如hope,want,expect, think,mean,suppose,intend,plan等后接从句时,一般用过去完成时表示本打算实现而未实现的愿望和计划。
eg I had intended to meet him at the airport, but I had an important meeting to attend.
(我本打算去机场接他,但是我有个重要的会议要参加。)
I had hoped to take a holiday this year but I was not able to get away.
(我原打算今年去度假,可是我离不开。)
4. 在句型hardly…when和no sooner…than中,主句用过去完成时,从句用一般过去时,表示“一……就……”。
eg Hardly had I left when it began to rain.
(我刚离开就开始下雨了。)
No sooner had he sat down than the telephone rang.
(他刚坐下,电话铃就响了。)
注意部分倒装
5. 过去完成时还可用于一些固定句型:
◆It was the first time that从句,that从句谓语常用过去完成时。
eg It was the first time that we had been to Chicago.
◆It was + 一段时间+ since从句,从句谓语用过去完成时。
eg It was two years since he had joined the army.
一般过去时与过去完成时的区别
一般过去时 过去完成时
只强调过去某一特定的时间 在时间上强调“过去的过去”
当两个或两个以上接连发生的动作用 and 或 but 连接时,按时间顺序,只需用一般过去时 在 after , as soon as 引导的从句中,由于这些连词本身已经表示出时间的先后,因此也可以用过去时来代替过去完成时
在没有明确的过去时间状语作标志时,谓语动词所表示的动作发生的时间先后须依据上下文来判断:先发生的用过去完成时,后发生的则用一般过去时。 eg They had arrived at the station by ten yesterday.
They arrived at the station at ten yesterday.
He entered the room, turned on the light and read an evening paper.
Supplementary explanation
现在完成时与过去完成时的区别
现在完成时 过去完成时
站在“现在”的角度回顾过去,表示一个从过去持续到现在的动作或事件,对现在仍有影响 站在“过去”的角度回顾一个更远的过去,强调“过去的过去”。只有和过去的某个时间或某个动作相比较时,才用到它。
have (has) + 过去分词 had +过去分词
时间状语常用today, this week, this year, recently等 时间状语常用by, by the end of, by the time, before, when等构成的短语或从句
eg We have lived here for ten years.
We had lived here for ten years when we had to move last year.
I have learnt 2,000 English words so far.
I had learnt 2,000 English words till then.
Have you read the newspaper today
By the end of August, they had treated over 5,000 patients.
过去式
Yuan Longping _________ to do research on hybrid rice because natural disasters __________ food shortages in the 1960s. In the end, he ___________ a better type of rice.
began
had led to
developed
First
then
led to food shortage →began to do research
→developed a better type
1. a Natural disasters led to food shortages in the 1960s.
b Yuan Longping began to do research on hybrid rice.
c Yuan Longping developed a better type of rice.
01
2
03
0
4. The police found the lost boy. He______ (run) away from home five days before.
5. This was the first time I ______ (come) to your hometown.
6. Tom had to correct the mistakes in his composition(作文) that his teacher ______ (point) out.
had run
had come
had pointed
0
翻译句子
我们到达火车站之前,火车就已经离开了。
Before we got to the train station, the train had already left.
我还没来得及说谢谢,他就跑开了。
Before I could say "thank you", he had run away.
画出标志词\短语:
a. By the end of last term, we had learnt 2,000 English words. 到上学期期末为止,我们已经学习了2,000个英语单词了。
b. They had lived there for ten years by then. 到那时为止,他们已经在那里住了10年了。
画出标志:
a. Hardly had I left when it began to rain.我刚离开就开始下雨了。
b. No sooner had he sat down than the telephone rang.他刚坐下,电话铃就响了。