课件22张PPT。Unit2 Saving the EarthTopic2 All these problems are very serious.Section C何坝九校梅文政In our daily life, we should face more environmental problems.
Can you say something about them? cities, pollute, health problemsIn our daily life, we should face more environmental problems.
Can you say something about them? factories, the land and the air, deadIn our daily life, we should face more environmental problems.
Can you say something about them? cut down, millions of,
take away the earth,
become desertIn our daily life, we should face more environmental problems.
Can you say something about them? oxygen a special kind of oxygen['?ksid??n]
called “ozone” (O3) a very big hole in the ozone layer,
too much harmful radiation from the sun臭氧层视频In our daily life, we should face more environmental problems.
Can you say something about them?CO2 carbon dioxide [dai'?ksaid] 二氧化物
increase a lot, form a “blanket”,
the heat from the sun can’t escape cause the level of the sea to rise
called “the greenhouse effect”
or “globe warming”温室效应：What other kinds of environmental problems
can you think of?
Talk about them with your classmates.fewer treesfactory pollutiontraffic pollutionthe ozone layermore carbon dioxideCan you match them?Fewer treesFactory
pollutionTraffic
pollutionThe ozone layerMore carbon
dioxideAll these problems are very serious. What can we do
to solve them?Read and understand（影片）Can you choose a suitable title for each paragraph from the phrases below? The earth is 4 600 million years old. We humans have lived on earth for only 35 000 years, but during this period we have changed our planet a lot in many ways. Some things we’ve done are very good for the earth while some 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 more and more sorts of animals and plants are disappearing.Fewer Trees ____________ In big cities, cars and buses have polluted the air. Many people in cities now 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 that has made 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 PollutionFactory 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 DioxideRead 1a again and choose the best answers.1、What does our planet mean here?
A. The sun. B. Mars.
C. The moon. D. The earth.
Read 1a again and choose the best answers.2、Which is NOT true?
A. Cars can pollute the air.
B. Factories can pollute the water.
C. The fewer trees, the better.
D. Not all the things we have done are good for the earth.
3、The word it in the passage refers to ____.
A. CO2 B. O3 C. O2 D. H2O
Read 1a again and choose the best answers.4、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
5、The level of the oceans is rising because of ____.
A. pollution B. few trees
C. the greenhouse effect D. changes in the climate
Read 1a again and choose the best answers.6、What is the best title for this passage?
A. Environmental Problems
B. Pollution on the Earth
C. Hope for the Future
D. The Greenhouse Effect
Ozone is very important to the earth. O3:Written workDiscuss the meanings of the following expressions and then write down how they affect the environment.A special kind of oxygen called “ozone”The ozone layer can prevent the sun's harmful radiation reaching the earth. But now air pollution is destroying the ozone layer. This is very dangerous because this kind of radiation can cause cancer. CO2:the greenhouse effect: More and more carbon dioxide forms a “blanket” around the earth.Written workDiscuss the meanings of the following expressions and then write down how they affect the environment.Carbon dioxide. It mainly comes from burning oil, coal and wood. Carbon dioxide around the earth makes the temperature rise. The heat from the sun can't escape so the temperature is rising. It causes the level of the oceans to rise and the climate of the earth to change.Group work
Are you a green person? Do you want to know how many people are turning green in your class? Work with your partners and design a questionnaire(问卷调查) like this.
How many kinds of pollution do you know?
…Useful expressions… people have cut down millions of trees.
… the earth is taken away.
The heat from the sun can’t escape so the
temperature is rising.
It causes the level of the oceans to rise …Bye-bye!课件介绍及使用说明
本课件是为仁爱英语九年级上学期Unit2 Topic2 All these problems are very serious. Section C编写的教学课件。本课时课本只安排了两个教学片段，一个是对已学的环境污染类型的总结，同时还增加了臭氧层和二氧化碳等热门环境问题；另一个教学环节是一个综合探究活动，让学生根据所学内容对新学习的环境污染类型进行讨论并形成文章。为了让学生能够更加生动地理解人类所面临的环境问题，本课时除了运用大量的图片展示之外还增加了两个视频片段。
复习/导入----图片展示，学生讨论并形成语段表述。（幻灯片2-4）
呈现----①通过图片和视频让学生了解一些新的东西，一是臭氧层，一是二氧化碳。（幻灯片5、6。点击幻灯片5和6下方的文字链接相关视频，资源从“仁爱教育网”相应位置下载。）
②小组谈论常碰到的环境问题并完成连线任务。（幻灯片7、8）
③导入新课，（幻灯片9）教学课文。（幻灯片10。点击幻灯片10右上角的影片链接课本1a动画）
巩固----校对1a 答案，并让学生提出疑难点，老师进行解答。（幻灯片11-13）
练习----①再次详细阅读1a并完成练习，处理好1b。（幻灯片14-17）
②讨论完成课本2。（幻灯片18、19）
综合探究活动----①分小组活动，讨论并设计问卷调查，在课后完成调查任务。（幻灯片 20）
②学生小组总结本课重点句式。（幻灯片 21）
