1、Warming UpWhat are the planets in our solar system?水星水星Mercury金星金星地球地球火星火星木星木星土星土星天王星天王星海王星海王星Venus EarthMarsJupiterSaturnUranusNeptuneWhat interests you in astronomy?the Milky Way 银河银河star 恒星恒星planet 行星行星Plutocomet 慧星慧星shooting star/meteor 流星流星black hole 黑洞黑洞1.Have you ever asked your mother,“Mom,w
2、here do I come from”?2.Nearly everybody has this or that puzzles:How do human beings come into being?How does the earth come into being?Pre-readingReadingCan you predict the main idea of this text by looking at the tittle How Life Began on the Earth?the origin of earthRead the passage carefully and
3、analyse its structure.Find out the keywords of these paragraphs.Paragraph 1:Paragraph 2:Paragraph 3:Paragraph 4:Paragraph 5:Big Bangatmospherewaterplants and animalshuman beingsthe development of the earththe development of lifeStage 1:The development of the earth(1)After the Big Bang,what was the e
4、arth like at first?a cloud of dust a solid globe 4.5-3.8 billion yearsEarth()/exploded with fire and rock produced water vapour and gases(2)What happened next?(3)The water vapour and gases form the _.atmosphere(4)What appeared as the earth cooled down?water Why is water so important for the beginnin
5、g of life?Because water allowed the earth to dissolve harmful gases into oceans and seas.This produced a chain reaction,which made it possible for life to develop.Stage 2:The development of life small plants appears in water 1.What life developed after water appeared?Shellfish and all sorts of fish
6、2.What life developed in water next?green plants began to grow on land insects appeared3.What about the life on land?amphibians on land and in the waterforests4.What life developed next on land?reptiles appeared dinosaur developed 5.What life developed after forests appeared?mammals on land6.What li
7、fe developed after dinosaurs?small clever animals such as human beings7.What life developed after mammals?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 app
8、eared2.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.831091151741262Can you put the order of development of life into a time line?Can you put the order of development of l
9、ife into a time line?summaryAfter the“big bang”,the earth was still just a cloud of _,it _loudly with fire and rock,which were _ to produce the_,water vapour and other gases.Then _ began to appeared on the earth.dustexplodedin timecarbonwater _ in water are considered to be the earliest lives on the
10、 earth.The O2 they supplied encouraged the lives of_.Slowly green plants grew on land,which were followed by _like insects&_.When the plants grew into_,_ appeared.Then _ developed but disappeared later,which made the rise of a totally different animal,_,possible,and finally _ spread all over the world.shell-fish and fishamphibiansforestsreptilesdinosaursmammalhumansThe small plantsland animalsThank you
