1、Unit 4 Astronomy: the science of the stars,Reading,Read paragraph 1, and answer the following questions. 1.How did water come into being on the earth?2. What is the significance of the presence of water on the earth?,The explosion of the earth produced water vapour, which turned into water when the
2、earth cooled down.,It allowed the earth to dissolve harmful gases into oceans and seas.,Reading-II-skimming (3m),自主学习,Put the order of development of life into a time line. insects and amphibians appear a solid ball reptiles appear a cloud of dust shellfish and other fish appear dinosaurs appear sma
3、ll plants grow on the water plants begin to grow on dry land presence of water mammals (including humans )appear,D,B,I,G,E,H,A,C,F,J,反馈练习,Stage 1: The development of the earth,(1) After the Big Bang, what was the earth like?,a cloud of dust,a solid globe,合作探究,exploded with fire and rock,produced wat
4、er vapour and gases,(2) What happened next?,合作探究,Water appeared,(4) What appeared as the earth cooled down?,water is important for the beginning of life on the earth.,合作探究,Why is water so important for the beginning of life?Because water allowed the earth to dissolve harmful gases and acids into oce
5、ans and seas.,？,合作探究,Stage2 The development of life,small plants appears in water,1.What life developed after water appeared?,自主学习,Shellfish and all sorts of fish,2.What life developed in water next?,自主学习,green plants began to grow on land,insects appeared,3.What about the life on land?,自主学习,amphibi
6、ans on land and in the water,forests,4. What life developed next on land?,自主学习,reptiles appeared,dinosaur developed,5.What life developed after forests appeared?,自主学习,mammals on land,6.What life developed after dinosaurs?,自主学习,small clever animals,7. What life developed after mammals?,自主学习,What are
7、they doing on the earth?,合作探究,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 .,1. Insects and amphibians appeared. 3. The earth became a solid ball. 5. Reptiles appeared. 7. Th
8、e earth was a cloud of dust 9. 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 earth 10. The universe began with a “Big Band”. 12. Mammals appeared
9、.,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?直击高考,Ex.2 on P27,7. Conclude the main idea of each paragraph. 1) A widely _ about the _ of the universe. 2) The formation of the _. 3) The _ of water for life. 4) The development of _ and _ on the earth. 5) Th
10、e arrival of _ and their _ on the earth.The text mainly tells us the _ of the earth and the _ of life on it.,8. The main idea of Reading1.,Ex.1 on P27,theory,origin,earth,importance,plants,animals,humans,influence / effect,formation,development,直击高考,How life began on earth is one of the biggest puzz
11、les that scientists found hard to solve. What other puzzles are hidden in the passage?,Discussion,Ex.5 on P27,How does the universe(earth) form? Why did the earth cool down? Why did water disappear on other planet? How did the dinosaur disappear ?,合作探究,1. Finish the exercise 1and 2 on page 63 2. Read the text again and find out your difficult points.,布置作业Homework:,
