2. Unit 4 Astronomy: the science of the stars

3. How life began on the earth?

4. Do you know each religion or culture has its own ideas about the beginning of the universe? Please give an example if you know. Pre-reading

5. The beginning of the life Pangu separates the sky from the earth. 盘古开天 Nvwa makes human beings. 女娲造人 God created man. 上帝创世说

6. Para1 Big Bang atoms ____________ and________ to ____ stars and other bodies begin to form create According to a widely accepted theory,the universe began With________ combine

7. Paragraph 1: Paragraph 2: Paragraph 3: Paragraph 4: Paragraph 5: D.How the plants and animals on the earth developed. C. How the earth formed. A. How humans appeared and what effects they have caused to the earth. B. Water is very important for life on the earth E.It is widely accepted that universe began with a “ Big Bang ” Read quickly and match the main idea of each paragraph

8. Main idea: The text mainly tells us the __________ of the earth and the _____________ of life in it. formation development

9. 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. Mammals appeared before the development of dinosaurs. 5. Dinosaurs could give birth to young baby animals and produced milk to feed them. 6. Human beings produce too much carbon dioxide which causes the global warming on the earth. 7. According to the text, human beings would disappear in the end. F F T F F F T

10. TimeThe earth As the earth cooled down Several billion years after the “Big Bang” Between 4.5 and 3.8 billion years ago A cloud of dust A solid globe Exploded with fire and rock Water began to appear Produce C/N water vapor, etc. Stage1 The formation of the earth Para1-2

11. Why is water so important for the beginning of life? Because water allowed the earth to dissolve harmful gases into oceans and seas. Para3

12. Stage2 The development of life Para 4-5

13. Read para4 and fill in the blanks 4545 6 7 8 9 10 small plants in water insects reptiles amphibians mammals dinosaurs humans plantsanimals Green plants on land forests Shellfish and all sorts of fish 3 2 1

14. Put the order of development of life into a timeline according to the reading passage. 1. Insects and amphibians appeared. 3. The earth became a solid ball. 5. Reptiles appeared. 7. The 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 Bang". 12. Mammals appeared. 1073849615212 11 人类的 进化过 程.flv

15. 1.Who are the small clever animals with hands and feet? 2. Are they taking good care of the earth? Why? Para5

16. Because they are putting too much carbon dioxide into the atmosphere. The earth may become too hot to live on. Prevent heat from escaping from the earth into space

17. The earth is becoming hotter and hotter!

18. Whether life will continue on the earth depends on human beings. Only if ( 只要 )we care will we help, only if we help shall all be saved!

19. .