How-the-earth-began.ppt

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,Unit 4,How Life Began on the Earth,A Quiz,Game,1.How old is the earth?,A.About 3.5 billion years,B.About 4.5 billion years,C.About 5.5 billion years,D.About 6.5 billion years,2.,About_,of the earth surface is covered,by,water.,A.20%B.30%C.50%D.70%,3.How many planets are there in the Solar System?,A.6 B.7 C.8 D.9,4.What is the total population of humans on the earth?,A.About 3.5 billion B.About 4.5 billion,C.About 5.5 billion D.About 6.5 billion,5.How long does the rotation(,自转,)of the,earth,take?,A.12 hours B.24 hours C.a month D.365 days,6.,On,what day is the Earth day celebrated?,A.April 22 B.May 4,C.August 21 D.November 11,Main idea of each paragraph,Para.1 The formation(,形成,)of,the earth,.,Para,.2 The importance of,water for life.,Para,.3,A,widely accepted theory,about,the beginnings of the universe.,Para,.4,The,arrival of humans and,their,influence,on the earth.,Para,.5 The development of plants,and,animals on the earth.,Main idea of the reading passage:,the earth,life,Part 1 the formation of _,Part 2 the development of _,Detailed information,1.Big Bang,2.,a cloud of dust,3.,a solid globe,4.exploded with,fire and rock,5.produced carbon,nitrogen,water vapour,other gases-,atmosphere,Part 1,How did the earth come into being?,6.cooled down,7.,water,appeared,8.dissolved harmful,gases&acidwhich,made it possible for life to develop,Part 2,the development of life,1,2,3,4,5,6,7,8,9,10,extremely small,plants,in,water,early shellfish,and,all,sorts,of fish,insects,reptiles,amphibians,mammals,dinosaurs,humans,plants,animals,green,plants on land,forests,Listen to the reading passage.,While listening,look at the pictures on the screen which can help you understand the text better,.,Big Bang,Stars and other bodies,A cloud of dust,a violent solid globe,Explode with fire and rock,atmosphere,water,oceans and seas,extremely small plants in water,early shellfish and all sorts of fish,green plants on land,insects,amphibians,forests,reptiles,dinosaurs,mammals,1,.,Insects and,amphibians,appeared.,3.The earth became a solid ball.,5.,Reptiles,appeared.,7.The earth was a cloud of dust,9.,Shellfish,and other fish appeared.,11.,Clever animals,with hands and feet appeared,2.,D,inosaurs,appeared.,4.,S,mall plants,grew on the water.,6.,P,lants began to grow,on dry land.,8.,W,ater appeared on the earth,10.,T,he universe began with a“Big Band”.,12.,Mammals,appeared.,8,3,10,9,11,5,1,7,4,12,6,2,Can you put the order of development of life into a time line?,Ex.2 on P27,So,whether life will continue on the earth for millions of years to come,will depend on whether this problem can be solved.,We are making the world,better,.,We are making the world,worse,.,Discussion,What can we,do to,tak,e,care of,the earth?,solar energy,plant trees,recycle rubbish,save water,purify air,