Unit 2 Saving the earth. Topic 2 All these problems are very serious. Section A课件(共18张PPT)2023-2024

(共18张PPT)
Unit 2 Saving the Earth
Topic 2 Pollution has caused too many problems.
Section A
Language goals
By the end of the class, you will be able to
1.Master the following words ,phrases and sentences:
Words： sand, although
Phrases: change into, human being
Sentences：①As a result, a lot of rich land has changed into desert.
②Trees can stop the wind from blowing the earth away.
2. Know how sandstorms come into being.
3. Be able to use the indefinite pronouns correctly.
Revision：一般过去时和现在完成时的用法区别
一般过去时 现在完成时
用法
连用的词和短语
表示过去发生或已完成的动作
对现在的影响或产生的结果（与现在无关）
表示过去发生的动作或存在的状态（与现在无关）
yesterday,
last + 时间名词,
时间段+ ago,
in 2005,
in the past, just now …
for +时间段, since, recently,so far, already, yet, just, ever, never, before
in the past +时间段,
3. Do you know how sandstorms come into being Number the pictures and talk about the sandstorm in groups.
( )
( )
( )
( )
( )
( )
4
1
5
3
6
2
wash the earth away
many trees
change into desert
forests gone
sandstorms come into being
cut down trees
Long ago, there were lots of trees and forests. But human beings needed some wood to build houses and do other things, so they cut down the trees day by day. The forests have gone. The rain washed the earth away.A lot of rich land has changed into desert. As a result, the sandstorms come into being.
1. The boy and girls are talking about ___________.
different types of sandstorms
the reasons for sandstorms
sandstorms in different cities
2.What’s the weather like today
3.What causes these sandstorms
4.Do we still need to do something to protect the environment
1b Listen to 1a and choose the best answer.
B
It’s bad. The wind is so strong . And the sand really hurts face.
People have cut down too many trees.As a result, a lot of rich land has changed into desert.
Yes, we do. Although we have built “The Green Great Wall”, we still need
to do something to protect the environment .
Tree’s functions
A. Trees can stop the wind from blowing the earth away.
B. lot of water can be saved
by forests.
C. They can also stop the water from washing the earth away.
1c Read 1a and complete trees’ functions.
Key points
1. when 表示 “当......时候” + 延续性v./短暂性v.
while 表示 “当......时候” 只能 + 延续性v.
eg. 1.When/Whie Margo was talking on the phone, her sister walked in.
2. Cindy was wearing a pink shirt when I saw him.
▲ while “然而” ，表对比; “一边---，一边---”，表示两个动作同时发生。
2. change... into = turn... into 把......变成......
3. stop sb. (from) doing sth. 阻止某人做某事
= prevent sb. (from) doing sth.
= keep sb. from doing sth.
▲ keep sb. doing sth. 让某人一直做某事
4. cut down “砍倒” 代词放中间
5. a number of “许多” (修饰主语，谓语当做复数）
the number of “......的数量” (作主语，谓语用单数）
Key points
▲ 用what’s 来提问，用large/small来修饰。
eg. 1. A number of students __________ (have) the same problem.
2. The number of the students in our school ______ (be) over 3,000.
6. blow… away 吹走 wash …away 冲走
eg. 1. The wind will blow the earth away.
2. A lot of water will wash the earth away.
7. although 引导让步状语从句，意为“尽管，即使”，可换为 though /even though, 其后句中 不能出现but。
eg. Although there were sandstorms before, now we have built “The Green Great Wall"
8. V-ing作主语，谓语动词用单数
eg. Cutting down trees affects the weather so much.
9. be harmful to = do harm to 对...有害
10. be in danger (of) 处于(…的)危险中
have
is
Key points
11. plenty of…= a lot of …=lots of … 许多的 + 可数名词复数/ 不可数名词
eg. plenty of books/water
12. come to do sth 开始/逐渐做某事
e to understand 开始知道
13. 语法：不定代词
1）somebody, someone, something, somewhere 一般情况下用于肯定句
anybody, anyone, anything, anywhere 一般情况下用于否定句和疑问句
none, nobody, nothing, nowhere 表否定含义
everybody, everyone, everything, everywhere 可用于各种句式
2）形容词、动词不定式修饰不定代词、副词时，应置于不定代词、副词之后
eg. I have something important to tell you.
3）不定代词作主语时，谓语动词要用单数
eg. Something is in the box.
Use someone, something, anything, somewhere, anywhere to fill in the blanks.
Lily, would you like ___________ to drink
Cindy is very busy now. She needs __________ to help her.
Is there _________ wrong with your computer
Jim looked for his pencil-box ____________ , but he didn’t find it.
I stayed at home last week. I didn’t go __________.
something
someone
anything
somewhere
anywhere
as a result, change into, do something, stop…from, blow…away
1.People have cut down such a large number of trees that the land
________________desert.
2.There are fewer trees left, so the wind always _______the earth ________.
3.Air pollution has become a serious problem, so we must______________
to reduce it.
4.we should try our best to _________ people ________ cutting down the trees.
5.In the future, human beings can protect the trees well.
_____________, animals will live a happy life in the forest.
has changed into
blows
away
do something
stop
from
As a result
2. Complete the sentences with the correct forms of the given phrases in the box.
4. A. Listen to the passage and circle the phrases you hear.
become weaker destroy the environment
disappear rapidly on the earth
enough bamboo to eat
B. Listen again and fill in the blanks.
1. Now some kinds of animals are becoming ______ ______ _______.
2. Some animals are_______ ________ ______dying out completely.
3. In the past, pandas lived a quiet life and had________ ______food.
4. Humans have _____ _____ __________ the importance of protecting animals.
5. We should ______ ______ ____to protect them.
do our best
in danger of
plenty of
come to understand
fewer and fewer
1.刚才
2.变成/转换成
3.阻止某人做某事
4.对......有影响
5.把......冲掉/洗掉(吹走，带走）
6.许多（谓语v.用复数）
7.......的数量（谓语v.用单数）
8.灭绝
9.砍倒
10.结果
11.对...有害
12.开始存在，产生
13.处于(…的)危险中
14.开始/逐渐做某事
15.足够的，大量的
1.just now = a moment ago
2.change/ turn --- into ---
3.stop sb. from doing sth..（prevent/keep)
4.have an effect on = affect
5.wash...away(blow/take)
6.a number of + c.n.(pl)
7.the number of + the + c.n.(pl)
8.die out
9.cut down
10.as a result
11.be harmful to = do harm to
12.come into being
13.be in danger (of)
e to do sth.
15.plenty of
Exercises in class
Exercises in class
1. Our teacher have told us _____ the trees.
A. cut off B. cut down C. not to cut off D. not to cut down
2. ____ they can swim, ____ they never go swimming alone.
A. Although, but B. Though, but C. Although, / D. Because, so
3. The policemen tried to prevent traffic accidents _____ happening.
A. from B. in C. to D. with
4. He didn’t cross the road until the red traffic lights changed ____ green ones.
A. to B. into C. for D. in
5. _____ bad weather! We have to stay at home.
A. What a B. How C. How a D. What
6. I knocked on the door ,but ______answered.
A. somebody B. nobody C. anybody D. everybody
7. Your computer doesn’t work now ,is there _____with it
A. wrong something B. something wrong C. wrong anything D. anything wrong
8. -Would you like to have _____ -No, thank you. I’ve had enough.
A.anything more B.something more C.more anything D.more something
9. he driver was badly hurt ,_______he couldn’t walk any more .
A. at a result B.in the result C. with the result D.as a result
B
C
A
B
D
B
D
B
D
Summary
We learn: 1.Some words: sand, although
2.Some phrases: change into, human being
3.Some sentences:
(1)As a result, a lot of rich land has changed
into desert.
(2)Trees can stop the wind from blowing the earth away.
We can: 1. Use the indefinite pronoun and adverb.
2.Talk about the sandstorm and its harm.
Homework
1. Read 1a aloud&Learn the new words by heart.
2. Memorize the useful expressions and key sentences which we learn today.
3. Finish Section A in your workbook.
4. Preview Section B.