人教版英语必修3Unit4Reading课件.ppt

Unit 4,Astronomy,Whats the meaning of the word“Astronomy”?,I.Warming up,行星,the science of stars;,2.Do you know the following terms?,star,planet,the sun/moon/earth,solar system,太阳系,3.How many planets are in the solar system?,8,恒星,Pluto,Scientists now think Pluto is too small to be called a planet.,4.Do you know the correct order of their distance to the sun?,nearest to the sun?,farthest to the sun?,5.The names of eight planets.,MercuryVenusEarthMarsJupiterSaturnUranusNeptune,1)水星2)金星3)地球4)火星5)木星6)土星7)天王星8)海王星,In this unit,well learn something more scientific.1.Whats the title of the text?,2.From the title,we can predict that the text may tell us the origin of life on the earth.Do you know some stories about it?,How life began on the earth,Pangu separates the sky from the earth.,Nvwa made humans.,Fast reading,I.Read the passage and match the main idea with 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 formation of the universe.Para.4 The arrival of humans and their impact on the earth.Para.5 The development of plants and animals on the earth.,1.When did the“Big Bang”happen?,Read the passage quickly and answer the questions.,2.What form was the earth after the“Big Bang”?3.What made up the earths atmosphere,4.How did water come into being on the earth?,5.Whats the significance of the presence of water on the earth?,6.What was important to the development of fish?7.What made possible the rise of mammals on the earth?,8.Why are mammals different from all life forms in the past?,1.When did the“Big Bang”happen?It happened several billion years ago.,Scanning,Read the passage quickly and answer the questions.,2.What form was the earth after the“Big Bang”?The earth was still just a cloud of dust.3.What made up the earths atmosphere after the earth exploded?Carbon,nitrogen,water vapour and other gases.,4.How did water come into being on the earth?As the earth cooled down after it exploded,water came into being.,5.Whats the significance of the presence of water on the earth?It allowed the earth to dissolve harmful gases and acids into the oceans and seas.,6.What was important to the development of fish?oxygen.7.What made possible the rise of mammals on the earth?The disappearance of dinosaurs made the possible the rise of mammals on the earth.,8.Why are mammals different from all life forms in the past?They gave birth to young baby animals and produced milk to feed them.,Finish the Exercise 2 on the book according to the questions above.,Detailed reading,Stage 1:The development of the earthStage 2:The development of life,(para 13),(para 45),Stage 1:The development of the earth,(1)After the Big Bang,what was the earth like?,a cloud of dust,a solid globe,exploded with fire and rock,produced water vapour and gases,(2)What happened next?,(3)What did the water vapour and gases form?,the earths atmosphere,Water appeared,(4)What appeared as the earth cooled down?,water is important for the beginning of life on the earth.,Why is water so important for the beginning of life?Because water allowed the earth to dissolve harmful gases into oceans and seas.,？,Stage2 The development of life,small plants appears in water,1.What life developed after water appeared?,Shellfish and all sorts of fish,2.What life developed in water next?,green plants began to grow on land,insects appeared,3.What about the life on land?,amphibians on land and in the water,forests,4.What life developed next on land?,reptiles appeared,dinosaur developed,5.What life developed after forests appeared?,mammals on land,6.What life developed after dinosaurs?,small clever animals,7.What life developed after mammals?,1.Who are the small clever animals with hands and feet?2.Are they taking care of the earth well?Why?,?,Because they are putting too much carbon dioxide into the atmosphere,which prevents heat from escaping from the earth into space.,The earth may become too hot to live on.,Can you fill in the blanks?,2,3,45,6,78910,1 small plants in water,shellfish and all sorts of fish,insects,reptiles,amphibians,mammals,dinosaurs,humans,plants,animals,Green plants on land,forests,1.Insects and amphibians appeared.3.The earth became a solid ball.5.Reptiles appeared.7.The earth was a cloud of dust9.Shellfish and other fish appeared.11.Clever animals with hands and feet appeared,2.Dinosaurs appeared.4.Small plants grew on the water.6.Plants began to grow on dry land.8.Water appeared on the earth10.The 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,III.Fill in the blanks in the following form.,Atoms,violent,atmosphere,presence,acids,oxygen,shellfish,amphibians,Reptiles,existed,gave birth to,clever,dioxide,IV.True(T)or False(F).1.The earth appeared before the Big Bang happened.2.The original atmosphere consisted of nitrogen and oxygen.3.The main difference between the earth and other planets is that there is water on the earth.4.Life began in water and then on land.,F,F,T,T,5.Mammals appeared before the development of dinosaurs.6.Dinosaurs could give birth to young baby animals and produced milk to feed them.7.Human beings produce too much carbon dioxide which causes the global warming on the earth.8.According to the text,human beings would disappear in the end.,F,F,T,F,Phrases and Useful Expressions,circle around 绕转according to 根据 a widely accepted theory 熟知的理论in all directions 向着四面八方 in time 及时；终于cool down 冷却be fundamental to 对关键a chain action 连锁反应 make it possible forto do使可能 give birth to 生育11.prevent from 阻止做12.millions of years to come 未来的几百万年,Post-reading,We have only one earth!,Disscusing,What should we do for our earth?,You can use the following words or phrases to help you:,prevent from harmful global warming carbon dioxide in turn depend on as a result thus atmosphere,