高中英语必修三第四单元课件谷风教学

1、unit 4unit 4 astronomy: the science of the astronomy: the science of the starsstars1沐风教育what are the names of the eight planets that circle our sun? what is their order from the sun?2沐风教育3沐风教育地球地球 _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 _earthjupitermarsmercuryneptunesaturnuranusvenus4沐风教育1. h

2、ow old is the universe?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 talk5沐风教育ideas about h

3、ow life began6沐风教育 reading readinghow life began on the earthhow life began on the earth7沐风教育fast readinga brief introduction on how the universe developed and how life began on the earth.8沐风教育 careful readingpara 1: para 2:para 3:para 4: para 5: a widely accepted theory about the formation of the u

4、niverse.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 beings9沐风教育1. what is the o

5、riginal 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 p

6、ast?10沐风教育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 possible for life to

7、 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.11沐风教育4. which kind of life-being first appeared on the earth, plants or animals? why?at fi

8、rst, 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 their bo

9、dies and produce milk to feed them.12沐风教育 （ ）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

10、the 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 13沐风教育let review the evolution of life on the earth.14沐风教育after the “big ba

11、ng”, the earth was full of water.15沐风教育original cells appeared in the ocean.16沐风教育the cells in the water began to separate. small plants came into being.17沐风教育early shellfish and all sorts of fish18沐风教育some animals (amphibian & insects) came to land.19沐风教育reptile appeared. 20沐风教育dinosaurs 21沐风教育

12、mammals22沐风教育man had evolved from apes. 23沐风教育we are making the world better.we are making the world worse.discussion24沐风教育 because they are putting too much carbon dioxide into the atmosphere.the earth may become too hot to live on .25沐风教育the earth is becoming hotter and hotter!26沐风教育 solar energy

13、plant trees recycle rubbish prevent desertificationsave water purify airwhat can we do to take care of the earth?27沐风教育whether life will continue on the earth depends on human beings.28沐风教育精讲点拨精讲点拨 the earth became so violent that it was not clear whether the shape would last or not. what many scientists believe is that the continued presence of water allowed the earth to dissolve harmful g