Unit 12 Life is full of the unexpected A (Grammar Focus-4c) 课件

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Unit 12
Life is full of the unexpected
Section A Grammar focus -4c
Learning aims
1.Learn about past perfect tense.
2.Review of key structures.
3.能正确使用由when,before,as,by the time 引导的时间状语从句表示过去发生的事情，复习一般过去时态。
Grammar focus
When I got to school, I realized that I had left my backpack at home.
By the time I got back to school, the bell had rung.
Before I got to the bus stop, the bus had already left.
I was about to go up to my office when I decided to get a coffee first.
As I was waiting in line with the other office workers, I heard a loud sound.
第一类：
第二类：
把下列句子分类
Grammar focus
Discuss with your partner!
1、为什么主句和从句分别使用
一般过去时态和过去完成时态？
2、在使用不同时态时从句和主句的先后顺序？
When he came in, the students stood up.
When the baby saw her mother, she stopped crying
He was about to watch a movie when his parents knocked
at the door.
They were about to get on the bus when they heard
someone shout.
As I was standing in front of the teachers’ office, I saw a boy
fight with another boy..
As he was doing housework, a bird flew into the kitchen.
Q1：在以上时间状语从句中，主句和从句的动作是先后发生，还是同时发生？
Q2：主从句都使用过去时态的时间状语从句的引导词有什么？
Answers:1.在以上的时间状语从句中，主句和从句的动作都是同时发生，或者在进行一个动作时，另一个动作突然发生。
2.主句和从句都用过去时态的时间状语从句引导词有when, as等
●When I got up, I found that my brother had already taken a bath in the bathroom,
●When she got to the check-out, she realized she had left her purse at home.
●Before I arrived at the airport, the plane had already taken off.
●They had already had breakfast before they got to the hotel.
●Most of the guests had left by the time he arrived at the party.
●The film had already begun by the time I got to the cinema.
过去完成时的结构？
过去完成时的结构：
“助动词had+动词的过去分词”
●When I got up, I found that my brother had already taken a bath in the bathroom,
●When she got to the check-out, she realized she had left her purse at home.
●Before I arrived at the airport, the plane had already taken off.
●They had already had breakfast before they got to the hotel.
●Most of the guests had left by the time he arrived at the party.
●The film had already begun by the time I got to the cinema.
过去完成时的用法？
过去完成时的用法：
表示在过去某一时间或动作之前已经发生或完成了的动作。
表示动作发生在过去的过去
Grammar focus
●When I got up, I found that my brother had already taken a bath in the bathroom,
●When she got to the check-out, she realized she had left her purse at home.
●Before I arrived at the airport, the plane had already taken off.
●They had already had breakfast before they got to the hotel.
●Most of the guests had left by the time he arrived at the party.
●The film had already begun by the time I got to the cinema.
过去完成时的常见引导词有哪些？
有：by the time,when,before,by等
1.As he was doing housework, a bird flew into the kitchen.
2. The film had already begun by the time I got to the cinema.
Let’s compare!
两种时态的区别
一般过去时表示过去某时发生的动作或存在的状态
过去完成时表示过去某一时间以前（即过去的过去）
发生的动作或存在的状态
Make sentences using by the time or before.
4a
1. Tim went into the bathroom. Mary got up.
2. The coffee became cold. I put cream in the coffee.
3. The teacher collected the math homework.
I got to school.
1. By the time Mary got up,
Tim had already gone into the bathroom.
2. Before I could put cream in the coffee,
the coffee had become cold.
3. By the time I got to school, the teacher had
collected the math homework.
4a
Make sentences using by the time or before.
4. I completed the work for my boss. The workday ended.
5. The movie started. I arrived at the cinema.
6. My mother finished making the apple pie. I got home from my language course.
I had completed the work for my boss before the workday ended.
The movie had started before I arrived at the cinema.
By the time I got home from my language course,
my mother had finished making the apple pie.
finish在此处作及物动词,
意为“结束;完成" ,其后跟名词或动词-ing形式作宾语。
finish doing sth.意为"做完某事"。
Fill in the blanks with the correct forms of the words in the box.
4b
rush out forget arrive at go into show up find out
1.By the time I arrived at the party, everyone else _____ already _________.
2.When he put the noodles into a bowl, he realized he ____________ to add the green beans.
3. By the time my mother came back from the market, I ______ already ____________ the door to go for my piano lesson.
had
rushed out
shown up
had forgotten
had
show up意为“赶到;露面”
例: My best friend didn't show up on my birthday.
我最好的朋友在我生日那天没有来。
①show sb. around意为“带领某人参观"。
例: The guide showed us around the Summer Palace.导游带领我们参观了颐和园。
②on show意为“展览;展出"。
例: The beautiful pictures are on show in the museum.这些美丽的画正在博物馆展出。
③show sb. sth. = show sth. to sb.意为“给某人看某物"。
例: Can you show me your photos =Can you show your photos to me
你可以让我看一下你的照片吗
4b
4. Before she got to the airport, she ___________ about
the earthquake.
5. When she __________ the movie theater, she remembered
she had forgotten to feed her dog.
6. Before she got a chance to say goodbye,
he ____________ the building.
Fill in the blanks with the correct forms of the words in the box.
4b
rush out forget arrive at go into show up find out
had found out
had gone into
arrived at
get a chance to do sth.意为”得到机会做某事”，其中chance 为可数名词，意为"机会;机遇"。例: He got a good chance to learn from the workers.
4b
①chance意为“可能性”时，既可以作可数名词,又可以作不可数名词，
其中have chance of doing sth.表示“有做某事的可能性”。例: He has a chance of winning the match.
他有赢得比赛的可能性。
②chance意为"偶然;碰巧”时，为不可数名词，其中by chance意为”碰巧; 偶然”。
4b
Write two true statements and one false statement about your day
yesterday. Then ask your classmates to guess the false statement.
4c
1.By the time I left for school in the morning, ______
2.By the end of the school day, ____________
3.By dinner time , ____________
I had already had dinner.
I had already finished my homework
I had already eaten plenty of fruits.
I had got a story book from Jane.
I had finished the test
I had cleaned the classroom.
I had had too many bananas.
By the end of意为“到...时为止，....之前;到....结束时”。其后若接表示将来的时间，句子常用将来完成时;若接表示过去的时间，句子常用过去完成时。
4c
例: By the end of next week, | will have finished reading this novel.
到下周末，我将已读完这本小说。
By the end of last year, I had planted three hundred trees.
到去年末，我已经种了300棵树了。
用括号内所给词的适当形式填空
1.I (oversleep) yesterday, so I was late for class .
2.Look at the (burn)bank. It was on fire. Let's call 911 immediately.
3. By the time I got to the bus station, the bus (leave).
overslept
burning
had left
Let’s practice!
4. The doctor stick to_____ (work) even if he didn't feel well. I asked him to take a rest, but he refused.
5. They talked loudly and____ (wake) up the his mum.
working
woke
Let’s practice!
Thank you!