牛津深圳版八年级下 7.3 Unit 7 Grammar（课件）

(共25张PPT)
Unit 7 The unknown world
Grammar
牛津深圳版八年级下册
1. As all the seats were full he stood up.
2. The country is not strong because it is large.
3. This boy didn’t do his homework because of skating.
4. I was late because of the heavy traffic.
5. Since /As we’ve no money, we can’t buy it.
6. Since everyone is here, let’s start the meeting.
Read and pay attention to the words in red:
We call these sentences Adverbial clauses of reason .(原因状语从句）
1
课堂导入
Adverbial clauses of reason tell us why things happen. We usually use because, as and since to start adverbial clauses of reason.
Adverbial clauses of reason
2
课堂活动
Adverbial clause of reason Main clause
Because no one else saw these aliens,
I refuse to believe you.
As Since We can also put the adverbial clause of reason after the main clause.
Main clause Adverbial clause of reason I refuse to believe you because
no one else saw these aliens.
as since Things to remember
When we put the adverbial clause of reason at the beginning of the sentence, we often separate it from the main clause with a comma(,).
语 法 讲 解
A 原因状语从句
在句中表示原因、理由的从句叫原因状语从句。
1 引导原因状语从句的从属连词主要有because, since, as。
2 表示语气的强弱顺序是：because﹥ since﹥ as。
3 这些连词都不能和so连用。
4 当原因状语从句放于句首时，通常要用逗号与主句隔开。
引导词because
1 because强调明确直接的因果关系，回答“why”问题。如：
She didn’t come to school because she was ill.
她没来上学是因为病了。
— Why was he angry 他为什么生气？
— Because I was late. 因为我迟到了。
2 because从句可与for互换，但for是并列连词，连接的是并列句，并且在for前必须有逗号隔开。如：
We must start early because it will take us 3 hours to drive there.
我们要早点出发，因为开车去那儿要3个小时。
= We must start early, for it will take us 3 hours to drive there.
引导词since
1 since表示明摆着的理由或原因，常译为“既然”。如：
Since you have finished your homework, you can take a rest.
既然你已完成了作业，那就休息一下吧。
2 since还可引导时间状语从句，表示“自从……以来”。如：
We’ve known each other since we were children.
我们从孩提时代起就相识了。
引导词as
1 as语气最弱，表示附带说明的原因。如：
As you’re busy, you needn’t go to see him today.
你很忙，就没必要今天去看他了。
2 as还可引导时间状语从句，表示“当……的时候”、“随着……”。如：
He dropped the glass as he stood up. 他站起来时，把杯子摔了。
We get wiser as we get old.
随着年龄的增长，我们也变得聪明些了。
Tom
a We heard some voices speaking
a strange language.
b She heard a loud noise last night.
c No one else saw these aliens.
d An alien saw us and made a terrible noise.
Police officer
Why was Tina sure that something landed in the forest near the hills
Why did you and Tina hide behind some bushes
3 Why did you run away
Why did your father refuse to believe you
The police officer asked Tom some more questions about the aliens. Match the questions with the answer. Then use them to complete the police officer's notes with as, since or because.
1 （because）
Tom
b She heard a loud noise last night.
Police officer
1 Why was Tina sure that something landed in the forest near the hills
Tina was sure that something landed in the forest near the hills because she heard a loud noise last night.
2（as）
Tina and I hid behind some bushes as we heard some voices speaking a strange language.
Tom
a We heard some voices speaking a strange language.
Police officer
2 Why did you and Tina hide behind some bushes
3（Because）
Because an alien saw us and made a terrible noise, we ran away.
Tom
d An alien saw us and made a terrible noise.
Police officer
Why did you run away
4 （Since）
Since no one else saw these aliens, our father refused to believe us.
Tom
c No one else saw these aliens.
Police officer
4 Why did your father refuse to believe you
Because of
Read the following sentences and find the difference.
Tim didn’t go to school yesterday because he was ill.
Tim didn’t go to school yesterday because of his illness.
We can also use because of to give the reason for something.
They went to the forest because of their curiosity.
Tina woke up at midnight because of a loud noise.
She decided to explore the forest because of it.
We can use a noun, a noun phrase or a (subject pronoun/ object pronoun) after because of.
Work out the rule
B because与 because of的区别
because和because of的意思都是“因为；由于”。 但because 是连词，其后接句子。because of 是复合介词，其后接名词、代词、动名词、what 从句等。如：
She doesn’t go to school because she is ill.
= She doesn’t go to school because of her illness.
她没来上学因为她生病了。
根据题目要求，完成下列句子。
1. The football match was put off. It rained.(用because连接句子)
2. Jim couldn’t walk because his leg was broken. (用because of改写句子)
Jim couldn’t walk _______________________ .
3. Many people give up smoking because smoking has harmful effects. (用
because of改写句子)
Many people give up smoking ___________________ .
because of its harmful effects
The football match was put off because it rained.
/ Because it rained, the football match was put off.
because of his broken leg
Write sentences about the story on page 99 by using because of.
1. Tina was surprised/the yellow light in the sky
Tina was surprised because of the yellow light in the sky.
2. The aliens landed on this planet/an accident
The aliens landed on this planet because of an accident.
3. The children ran away from the forest/the aliens
The children ran away from the forest because of the aliens.
4. Their dad was not sure about the children’s story/the writing on the piece of paper
Their dad was not sure about the children’s story because of the writing on the piece of paper.
3
课堂小结
1.We have learned how to use adverbial clauses of reason.
2. We have learned to give reasons with because of.
一、选择最佳答案填空。
( )1. I called the police ____ the terrible noise.
A. because of B. because C. since D. as
( )2. ____ I’m very tired, I am going to bed early.
A. Until B. As C. Though D. While
( )3. ____ no one knows the truth, we don’t believe what he said.
A. Whether B. When C. While D. Since
( )4. We believe there are aliens ____ these photos of UFOs.
A. since B. because C. as D. because of
D
A
B
D
4
课堂练习
（二）句型转换。
1 The students didn’t need to go to school because there was a storm.
The students didn’t need to go to school __________ ____ the storm.
2 He was ill, so he didn’t go to school.
__________________ he was ill, he didn’t go to school.
3 He couldn’t walk because his leg was broken.
He couldn’t walk ____________ ____ his _________ leg.
4 I came back because it was raining heavily.
I came back ___________ ____ the ________ rain.
5 My parents were angry because of my poor marks in the exam.
My parents were angry _________ I got poor marks in the exam.
because of
Because / Since
because of broken
because of heavy
because
（三）完成句子。
1 他因为一场事故失去了双亲。
He lost his parents __________ _____ an accident.
2 既然你已经在这儿了，何不多待两天？
____________ you are here, why not stay for two more days
3 你生病了，最好去看看医生。
____________ you are ill, you’d better go to see a doctor.
4 我没去那里，因为我不想见到他。
I didn’t go there _________ I didn’t want to see him.
5 因为要赶去火车站，他们很早就起床了。
_________________ they needed to go to the train station, they got up early.
because of
Since / As
Since / As
because
Because / Since / As
谢谢
21世纪教育网（www.21cnjy.com)
中小学教育资源网站
兼职招聘：
https://www.21cnjy.com/recruitment/home/admin