Unit 2 Saving the earth. Topic 2 Section C 课件(共23张PPT) 2024-2025学年英语仁爱版九年级上册

(共23张PPT)
Unit 2
Saving the Earth
Topic 2
Section C
1.学习目标
3.重点探究
2.自主学习
学习导航
5.当堂检测
6.课堂总结
4.拓展提升
新课导入
学习目标
1. 能熟悉并正确运用本课时的重点单词和短语
2. 能进一步学习各种污染对地球造成的危害
和造成这些污染的原因
3. 能根据不同的阅读目的，运用简单的阅读策略
获取信息
自主学习
Key words
take away 拿走
oxygen n. 氧气
hole n. 洞，坑
ozone layer 臭氧层
radiation n. 放射，放射物
directly adv. 直接地
carbon dioxide 二氧化碳
自主学习
Key words
form v. （使）出现
n. 种类；形式
blanket n. 毛毯，毯子
escape v. 渗出；逃跑；逃脱
rise v. 上升；起床；升起
the greenhouse effect 温室效应
refer to 提到，涉及，有关
重点探究
1a Read and understand.
Look at the following pictures and predict the main idea of the passage.
fewer trees
factory pollution
traffic pollution
the ozone hole
more carbon dioxide
The earth is 4.6 billion years old. We humans have lived on the earth for only 35 000 years, but during this period, we have changed our planet a lot in many ways. Some things we have done are very good for the earth while others are bad.
___________ All over the world, people have cut down millions of trees. When it rains or when the wind blows, the earth is taken away. Forests have become deserts, so many kinds of animals and plants are disappearing.
Fewer Trees
______________ In big cities, cars and buses have polluted the air. Now many people in cities have health problems.
_______________ Factories have also polluted the land and the water. As a result, many rivers and lakes are now dead.
______________ Around the earth, there's a special kind of oxygen called “ozone”(O3). It is important to the earth. But now air pollution is destroying it and making a very big hole in the ozone layer. Too much harmful radiation from the sun passes through the hole and reaches the earth directly. This is very dangerous because this kind of radiation can cause cancer.
Traffic Pollution
Factory Pollution
The Ozone Layer
_________________ Carbon dioxide (CO2) in the air has increased a lot. It mainly comes from burning oil, coal and wood. This has formed a blanket around the earth. The heat from the sun can't escape so the temperature is rising. This is called “the greenhouse effect”. It causes the level of the oceans to rise and the climate of the earth to change.
All these problems are very serious, so we must do something now.
More Carbon Dioxide
1b Read 1a and complete the following tasks.
1. Choose suitable titles for Paragraphs 2-6. Then write it down in front of
each paragraph.
A. Traffic pollution B. Factory pollution C. Fewer trees
D. The ozone hole E. More carbon dioxide
2. What does our planet mean here
A. The sun. B. Mars.
C. The moon. D. The earth.
3. In the passage, blanket refers to ____.
A. carbon dioxide around the earth
B. the ozone layer in the sky
C. the forests around the world
D. pollution all over the world
※
※
3
4
2
5
6
4. The word it in Paragraph 5 refers to ____.
A. CO2 B. O3 C. O2 D. H2O
5. What is the best title for this passage
A. Environment Problems
B. Pollution on the Earth
C. Hope for the Future
D. The Greenhouse Effect
※
※
Watch the video about 1a and then act out.paying attention to the pronunciation and intonation.
1c Complete the notes according to 1a.
Problem Effect on the environment
fewer trees forests become deserts, animals and plants disappear
traffic pollution
greenhouse effect, level of oceans rising, climate change
… …
cars and buses pollute air, health problems
pollute land and water, rivers and lakes dead
harmful radiation reaches the earth, cause cancer
factory pollution
ozone hole
more CO2
2 Surf the Internet to collect more information about environmental
problems and effects. Then discuss the information in groups and
take notes.
3 Combine the key points in 1c and 2 to form a short passage and pay attention to the proper linking words.
As we all know, water pollution is becoming more and more serious. Some factories pour waste water into the rivers. As a result, it makes the water dirty and smell terrible. Most of fish in the water have died and we can’t swim in the water. Water is very important to human beings, so we should do our best to protect and save it. Luckily, our government is taking measures to protect the water from pollution.
You can write it like this:
拓展提升
Language points
1. The earth is taken away. 泥土被带走。
take away 拿走、带走
Eg: 难道你要拿走他们的铅笔吗？
Are you goingt to their pencils
take away
2. As a result, many rivers and lakes are dead.
结果，许多河流和湖泊都死了。
※ as a result 因此，结果
Eg: 因此，他们会非常具有说服力。
, they can be very persuasive.
As a result
※ be dead
死气沉沉
pass through the hole 穿过洞
pass through
Eg: 空气可以通过潮湿的布料。
Air will the wet cloth.
pass through
4. Too much harmful radiation from the sun passes through the hole and reaches the earth directly.
来自太阳的太多有害辐射穿过该孔并直接到达地球。
穿过
4. It causes the level of the oceans to rise and the climate of
the earth to change.
它导致了海平面的上升以及地球气温的变化。
the level of the oceans 海平面
cause 造成 、 使(发生)
Eg: 吸烟可导致肺癌。
Smoking may cause lung cancer.
Eg: 这个坏消息使她伤心。
The bad news caused her to be sad.
※ cause… to do…
※ cause sth.
当堂检测
根据汉语完成句子。
1.绿色的长城已挽救数以百计的农田。
The Green Wall has saved ________ ____ field.
2.他在树下挖了两个深洞，然后把钱放进去。
He dug two _____ _____ under the tree , and then put the money into them.
3.很多古老的习俗正在消失。
Many old customs ____ _______ _____.
4.如果你感觉冷，你可以把那个厚毛毯盖在身上。
If you feel cold , you can put that ______ ________ on your body.
5. 由于温室效应，气候变得越来越暖了。
Because of ___ __________ _____ , the ______ is getting warmer and warmer.
millions of
deep holes
are dying out
thick blanket
the greenhouse effect climate
课堂总结
Unit 2
Topic 2 Section C
重点单词短语：
cause; take away;
as a result; pass through;
the level of the oceans
各种污染对地球造成的危害和造成这些污染的原因