Unit Three Understanding Science

1. Unit Three Understanding Science

2. Teaching objectives • Get a general idea about Stephen Hawking • Understand the main ideas and structures in Text A • Appreciate the style differences between narrative writing and expository writing • Grasp the main language points

3. Warm-up Activity Brainstorm some of the scientific and technological inventions. Discuss: In what way do scientific discoveries change our lives for the better or for the worse? Make a brief introduction to Stephen Hawking

4. Brainstorm some of the scientific and technological inventions. E-mail nanotechnology clone telephone Genetic engineering TV Laptop computer

5. In what way do scientific discoveries change our lives for the better or for the worse? Take one invention for example.

6. People must understand that science is inherently neither a potential for good nor for evil. It is a potential to be harnessed by man to do his bidding. -----Glenn T. Seaborq

7. A brief introduction of Stephen Hawking Read the passage on P279 and answer the following three questions. • What do many people find most striking about Hawking? It is the contrast between the strength of his mind and the weakness of his body. 2. How does Hawking communicate with others? He uses a computer that enables him to select words which are then turned into speech. 3. What are his main achievements?

8. Singularity:大星燃烧耗尽会继续坍缩直至达到具有无限密度的奇点，这个奇点，引力场特别强大使得光线不能从围绕它的区域逃逸，而被引力场拉回去。这就叫做黑洞 . • Black hole: Objects from which nothing was supposed to be able to escape任何物质一旦进入黑洞之后将会不能逃出而最终消失黑洞不是完全黑的。在宇宙意义的微观尺度上，粒子和辐射可以从黑洞漏出来。黑洞附近的强大引力场引起粒子反粒子对的创生，粒子对中的一颗粒子落进黑洞，而另一颗逃到无穷远去，逃逸的粒子好象是从黑洞里发射出来的，也就是说，黑洞象一个热体似的在辐射，这就是著名的霍金辐射。 • A Brief History of Time:时间简史

9. What impress us most is Hawking’s optimism.

10. Although there was a cloud hanging over my future, I found, to my great surprise, that I was enjoying life more than before.

11. At the beginning of A Brief History of Time, Hawking writes • “有人告诉我，我在书中每写一个方程式，都将使销量减半。于是我决定不写什么方程。不过在书的末尾，我还是写进一个方程，爱因斯坦的著名方程E=mc2。我希望此举不致吓跑一半我的潜在读者。” • I was advised that each equation I included would halve the sales. I included one equation. Einstein’s famous equation, E=mc2. maybe I would have sold twice as many copies without it.

12. In-class Reading Compare Unit 2 and Unit 3 to see the differences between narration and exposition (Video Tape) Analyze the text structure Read each part in Detail

13. The style of expository writing • Longer paragraphs in which there are longer and more involved sentences. • Closely packed • Third-person narration—for the purpose of objectivity • Sentences in the passive voice • Structure: A statement of opinion Supporting details a conclusion

14. Text Orgnization The public needs education in science so as to make informed decisions on their fate 1--3 4--6 The way to educate the public are detailed. Human civilization will survive if the public understand science well. 7

15. Exercises on Part 1 Answer the following four questions. • What’s the attitude of some people towards the change brought about by science and technology? • What was life like before science and technology began to change our life? • What would happen if all government money for research were cut off? • Is it possible to prevent science from further development? Why or why not?

16. Exercises on Part 2a. Mini-exposition What can be done to give the public the scientific background it needs to make informed decisions on science? 1.Science education in schools 2. Replacing equations with words and diagrams 3. Making use of popular media such as newspapers, magazines and above all TV.

17. b. Difficult sentences • Explain the underlined words:A qualitative grasp of scientific concepts is sufficient.(L47) • Analyze the structure of the following sentences: • But the rate of scientific progress is now so rapid that there are always new developments that have occurred since one was at school or university. (L50) • Genetic engineering and computers are two of the developments most likely to change the way we live in the future. (L53) • Translate the following sentences: • Maybe I would have sold twice as many copies without it. (L43) • Only television can reach a truly mass audience. (L57) • But others present scientific wonders simply as magic, without explaining them or showing how they fit into the framework of scientific ideas. (L60)

18. c. Cultural words • Acid rain • Greenhouse effect

19. Acid rain, a serious threat around the world, occurs when sulfur dioxide (二氧化硫) and nitrogen oxide (氧化氮)emissions from automobiles and fossil-fuel burning power plants which react (起反应) in the atmosphere (大气层) with water, oxygen, and oxidants (氧化剂) to form various acidic compounds (化合物) fall back to Earth as acidic precipitation (雨或雹). • Production of food crops has declined . • Causes acidification (成酸性) of lakes and streams and contributes to damage of trees at high elevations (海拔) . • The surfaces of great art and architectural treasures has been eroded(腐蚀), including the ancient sculptures of Rome and the Sphinx in Egypt.

22. Greenhouse effect • 1. Solar energy enters atmosphere.(大气层) unaffected (未受影响的) by greenhouse gases. • 2. Solar energy is absorbed (吸收) by the earth and re-radiated (再辐射) back to space of longer heat wavelengths (波长) . • 3. Greenhouse gases absorb heat radiation and re-radiate (再辐射) some of it back to the surface, much like an insulating (绝缘的) blanket (毯). • 4. Higher concentrations (浓度) of greenhouse gases trap (挡住，拦住) more re-radiated heat, causing temperatures in the lower atmosphere and of the earth's surface to rise.

23. Exercises on Part 3 T/F (Video Tape)

24. After-class activity • Useful expressions • Retell the text • Debate • Check exercises

25. Should cloning of human beings be banned?

26. Find out useful expressions from the exercises

27. Reasonable price Grasp the seriousness of the problem Commit the crime Sufficient evidence against sb. Timely help Economic development The board of directors Open a branch office Ensure sb. Sth Be dismissed Be vital to Hold an election Raise a question On the basis of Despite the fact that Make predicate predictions Line of products Regain one’s health Mountainous region Trained doctors Survive the car accident Release sb. From prison Further negotiation Have difficulty doing sth. Support military action Peaceful solution

28. Meet one’s requirements As is shown by history With the improvement of the standard of living Local clashes Dial a wrong number Go on a diet In the last two decades Reform and open policy A great success Substantial cut in In the coming year Human rights situation Joint venture Not because of …but because of Lack of capital Poor management Have the right attitude toward sth. Latest developments Rely on Lengthen one’s life Daily life

29. Useful sentences • The job is great in terms of advancement but the starting salary is rather low. • The lawn was laid out in the form of figure 8. • Words cannot convey how grateful we are for his timely help. • No living thing can do without air and water. • Mary is undecided about whether to stay on in her present post or to find a new job. • As is proved by the records, china’s human rights situation has been steadily improving over the years. • What we learn in school is no longer sufficient to last a lifetime.

30. Prefix

33. Assignments • Writing based on the debate • Prepare for Unit Four American Dream

34. Go,go,go!

35. Topic sentence • Topic sentence--the sentence containing the topic. It tells the reader what the paragraph is about, so it acts as a kind of signpost. • Supportsentence—the other sentences telling us more about the topic. • Two ways of writing down the topic of a paragraph: • a noun or noun phrase, such as: examples, causes, other causes • A question. For example: Why is the world getting hotter?