高中英语教学：book 3 unit 4.docx

Book 3 Unit 4 Part I：Warming up, reading and using language. 1. in our solar system 2. the origin of life on earth 3. according a widely accepted theory 4. fill the oceans and seas with oxygen 5. for the first time 6. exist on the earth 7. give birth to young baby animals 8. put too much carbon dioxide into the atmosphere 9. prevent heat from escaping from the earth into space 10. as a result of this 10. be lucky enough to have a chance to do sth. 11. get close to the moon 12. after a while 13. get the hang of 14. explain sth. to sb. 15. enjoy ourselves 重点句子背诵： What is even more important is that as the earth cooled down, water began to appear on its surface. Whether life will continue on the earth for millions of years to come will depends on whether this problem can be solved. It was not immediately obvious that water was to be fundamental to the development of life. This produced a chain reaction, which made it possible for life to develop.