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1、How much do you know about the universe?What are the names of the eight planets that circle our sun?What is their order from the sun?第1页/共30页第2页/共30页地球地球 _木星木星 _火星火星 _水星水星 _海王星海王星 _土星土星 _天王星天王星 _金星金星 _EarthJupiterMarsMercuryNeptuneSaturnUranusVenusTHE SOLAR SYSTEM 第3页/共30页1.How old is the universe?2
2、.How old is the earth?3.Which were the first creature or plants on earth?4.Do you know what the order for the development of plants and animals is?Several billion years ago.Between 4.5 and 3.8 billion years ago.Very small air-breathing creatures.Free Talk第4页/共30页Ideas about how life began第5页/共30页 re
3、adingHow Life Began on the Earth第6页/共30页Fast readingRead the passage quickly and find the main idea.A brief introduction on how the universe developed and how life began on the earth.第7页/共30页 Careful readingPara 1:Para 2:Para 3:Para 4:Para 5:A widely accepted theory about the formation of the univer
4、se.The formation of the earth.The importance of water for life.The development of plants and animals on the earth.The arrival of humans and their impact on the earth.Read the passage carefully and analyse its structure.earth,atmosphere and waterlife developmenthuman beings第8页/共30页1.What is the origi
5、nal earths atmosphere made up of?2.Why did scientists believe water is fundamental to the development of life?3.How did water come into being on the earth?4.Which kind of life-being first appeared on the earth,plants or animals?Why?5.Why were mammals different from all life forms in the past?Answer
6、the following questions.第9页/共30页Carbon,nitrogen,water vapour,and other gases.2.Why did scientist believe water is fundamental to the development of life?Because water allowed the earth to dissolve harmful gases and acids into the oceans and seas to ensure a following chain reaction,which made it pos
7、sible for life to develop.1.What is the original earths atmosphere made up of?3.How did water come into being on the earth?The explosion of the earth produced water vapor,which turned into water when the earth cooled down.第10页/共30页4.Which kind of life-being first appeared on the earth,plants or anim
8、als?Why?At first,small plants began to appear on the surface of the water,they produce oxygen,which encouraged the later development of early shellfish and all sorts of fish.5.Why were mammals different from all life forms in the past?They were different because they produced their young from within
9、 their bodies and produce milk to feed them.第11页/共30页（）1 Insects and amphibians appeared.（）2 Dinosaurs appeared.（）3 The earth became a solid ball.（）4 Small plants grew on the water.（）5 Reptiles appeared.（）6 Plants began to grow on dry land.（）7 The earth was a cloud of dust.（）8 Water appeared on the
10、earth.（9 Shellfish and other fish appeared.（）10 The universe began with a“Big Bang”.（）11 Clever animals with hands and feet appeared.（）12 Mammals appeared.875）64110392 Put the order of development of life.12 11 第12页/共30页Let review the evolution of life on the earth.第13页/共30页After the“Big Bang”,the e
11、arth was full of water.第14页/共30页Original cells appeared in the ocean.第15页/共30页The cells in the water began to separate.Small plants came into being.第16页/共30页Early shellfish and all sorts of fish第17页/共30页Some animals(amphibian&insects)came to land.第18页/共30页Reptile appeared.第19页/共30页dinosaurs dinosaur
12、s 第20页/共30页mammals第21页/共30页Man had evolved from apes.第22页/共30页We are making the world better.We are making the world worse.Discussion第23页/共30页 Because they are putting too much carbon dioxide into the atmosphere.The earth may become too hot to live on.第24页/共30页The earth is becoming hotter and hotter
13、!第25页/共30页 solar energy plant trees recycle rubbish prevent desertificationsave water purify airWhat can we do to take care of the earth?第26页/共30页Whether life will continue on the earth depends on human beings.第27页/共30页精讲点拨The earth became so violent that it was not clear whether the shape would las
14、t or not.What many scientists believe is that the continued presence of water allowed the earth to dissolve harmful gases and acids into the oceans.分析句子：第28页/共30页Homework1.A composition about What we can do to take care of the earth?2.Read and retell the passage to learn the important and difficult language points.第29页/共30页感谢您的观看！第30页/共30页