必修3 Unit 4 Astronomy: the science of the stars课件

课件25张PPT。Unit 4 Astronomy: the science of the starsUnit 4 readingHow Life Began on the Earth 【学习目标】： 1、正确理解本文内容，扎实掌握单词、短语、句型的用法；提升语言运用能力。 2、自主学习，合作探究；有效阅读，进一步训练阅读及写作技能，逐步培 养应用语言的综合能力。 3、在运用中学习英语，感受用英语表达思想的快乐。Task 1 Skimming (1).The text maily tells us how the earth came into being and the development of life on it. (2). B (3). B Task 2 Scanning (1).D (2).C (3). A Task 3 Scanning (1).F (2). F (3). T (4). T (5).F自主学习课内探究点评与质疑点评同学: 1、点评时声音洪亮，注重自己的“教态”,要 面向全体同学。 2、点评方法：先评对错、后总结拓展，打出分数。 3、点评讲究效率：言简意赅，遇不明白时及时请老 师解决。 非点评同学： 拿好红笔随时记录，并及时提出质疑与补充。 我是大评委！！我是大评委！！The "Big Bang "A cloud of dust A solid ballAtmosphere water appeareddissolve harmful gases and acids First,_____made it possible for life to begin to develop.waterNext,small plants grew on the water,which encouraged the development of _____.early shellfish and all sorts of fishLater _____ appeared. land animals insectsamphibiansWhen plants grew into forests, _____ appeared for the first time.reptilesAfter that , some huge animals, called _____, developed.dinosaursWhen dinosaurs disappeared, _____ became more important. mammalsFinally, _____ appeared and _____ all over the earthspreadhuman beingswater 1. 2. 10. 3. 4. _____ (on land) 5. 6. _____7._____ 8. dinosaurs (on land) 9._____ 11. small _____ in water_____ and all sorts of fishgreen _____ on land _____(on land and in water)forests (on land) (on land)small clever animals with _____plantsshellfishamphibiansreptilesmammalshands and feet A timeline of the development of lifeplantsinsects After the "big Bang",____ began to form and slowly the dust settled into a solid____. Then it exploded with fire and rock,which were to make the earth's_____. As the earth cooled down, water began to appear on its surface,which helped to dissolve harmful gases and _____. Later living things like plants,fish,insects,_____,_____appeared and developed. globeatomsatmosphereacidsamphibiansreptiles The disappearance of dinosaurs made possible the rise of _____ on the earth. Finally,some small clever animals with hands and feet appeared and they became the most important animals on the planet,but they are not taking_____of the earth very well.mammalscareBelieve in yourself! Show me your passion!RetellingWhat problem are these clever animals causing?They are putting too much CO2 into the atmosphere, which prevent heat from escaping from the earth.The earth may become too hot to live on . 拓展提升 飞扬你的思想！ What can we do to take care of the earth?Whether life will continue on the earth depends on human beings.Only if we care will we help, only if we help shall all be saved!We have only one earth!We should take care of the earth!ks5u精品课件Homework 1.Learn the useful words ,phrases and important sentences by heart. 2. Retell the p ... ...