九年级市观摩课教案.doc

Unit2saving the earthTopic 2 all these problems are very seriousSection C教案教学目标.知识目标：1. 学习重点单词： onearth,period,millionsof,takeaway,rise,level,referto2.学习关于污染危害的重点句型:(1)Whenitrainsorwhenthewindblows,theearthistakenaway. (2)The heat from the sunescapesothetemperatureisrising.(3)Toomuchharmfulradiationfromthesunpassesthroughtheholeandreachestheearthdirectly.(4)Itcausestheleveloftheoceanstoriseandtheclimateoftheearthtochange.II.能力目标：1. 学会利用本课重点句型谈论污染的危害。2. 通过本课学习提高学生的阅读理解能力，会概括段落大意。III.情感目标：1. 通过本课学习，提高学生保护环境的意识，增强学生保护环境的责任感。2. .通过小组活动，培养学生形成互学互助的合作意识，竞争意识及团结协作精神。教学重点：1.熟练阅读课文。2.学会利用本课重点句型谈论污染的危害。教具准备：多媒体课件教学过程：Step 1 情景导入，激发新知1.教师出示关于环境污染的图片，通过图片引导学生用英语谈论环境污染的危害。cities, pollute, health problems cut down, millions of, take away the earth,become desert2. 学生小组合作，用自己的话描述两幅图片，谈论污染的危害，形成短文。3. 各小组中心发言人展示合作的短文，教师给予鼓励。 Step 2 交流合作， 自主学习1. 学生小组合作自学1a，教师出示自学任务。Self-learning tasks: read 1a and try to translate 1a with your partner. choose a suitable title for each paragraph from the phrases below. finish the following questions. 1、What does our planet mean here? A. The sun. B. Mars. C. The moon. D. The earth. 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. H2O4、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 world5、The level of the oceans is rising because of _. A. pollution B. few trees C. the greenhouse effect D. changes in the climateStep 3 知识点拨，学习探究1.教师点拨短文中出现比较难理解的科普知识，教师出示关键词汇，引导学生复述。 CO2 carbon dioxide Increase a lot, form a “blanket”, the heat from the sun cant escape cause the level of the sea to rise called “the greenhouse effect” 2.教师讲解短文中的重点知识点。 die意为“死”，表示生命的结束，是不及物动词，不能用于被动语态； 强调动作，是瞬间动词，不能与表示一段时间的状语连用。 His father died five years ago. Plants and people die without water. die可以用于进行时态，表示“即将死去；奄奄一息” He is dying. die 的形容词形式是dead，意为“死的” His dog has been dead for two weeks. die的名词形式是death，意为“死亡” His mothers death was a great blow to him. 3.教师和学生一起讨论O3和CO2的作用。O3A special kind of oxygen called “ozone” The ozone layer can prevent the suns harmful radiation from 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: Carbon dioxide. It mainly comes from burning oil, coal and wood.More and more carbon dioxide forms a “blanket” around the earth. The heat from the sun cant escape so the temperature is rising. It causes the level of the oc