课件44张PPT。Unit 4By Kang Liweigreen house effectHow did the global warming come about?What about the weather?
2℃ / 10℃We need…Pre-reading ( 3m )The sun. How about the plants?GreenhouseWhat is the greenhouse made?What is the greenhouse used for?
A greenhouse is made of glass and is used for growing plants, especially during cold weather.How does it work?
The air inside is warm because the glass traps the heat from the sun and keeps it from escaping. This makes the greenhouse heat up and so the
plants can grow
throughout the
cold period.What are greenhouse gases?
What do you think greenhouse
gases do?
Greenhouse gases perform the same fun_ction as the glass in a glasshouse : They trap the heat of the sun and keep the air surrounding the earth warm, this is called greenhouse effect.So how has the greenhouse gases come about and does it matter?ReadingTHE EARTH IS BECOMING WARMER
— BUT DOES IT MATTER?Read the passage and try to find out the answers to the questions in Ex.1 on page 27.Reading I –scanning 1.Who wrote the magazine article? What is the name of the magazine?
2.What are the names of the three scientists mentioned in the article?
→ Sophie Armstrong, Earth Care.→ Dr Janice Foster, Charles Keeling, George Hambley.
→ There are some very different attitudes among scientists towards this issue. Some think the effects will be terrible, while some others believe that we should not worry about it.
3. What do they think about global warming? Do they agree with one another?→ The first graph shows the temperature increase of one degree Fahrenheit between 1860 to 2000. The second graph shows the carbon dioxide content in the atmosphere from 1957 to 1997.
→ Global warming / the warming of the earth4. What are the two graphs about?5. What is the main topic of the article?
Read the passage carefully and judge whether the statements are true or false?
1. The temperature in the last century did not seem to increase much.
2. Everyone believes that global warming is caused by the activities of humans.
3. Janice Foster believes that she can measure the future global rise in temperature.FTReading II-skimming T4. The rise in Carbon dioxide is causing a steady increase in global warming.
5. George Hambley believes that global warming will do good rather than harm to the earth.
6. It is clear what the effects of global warming will be.TTF
Tips:
We can divide the text into Four parts
Part 1 (para __)
Part 2 (para ___ to ___)
Part 3 (para ___ )
Part 4 (para ___ )
12567Reading III-detailed reading Main ideas of each part
Part 1: introduce a debate over the issue of global warming
Part 2:state how global warming comes about
Part 3:list two different attitudes among scientists towards global warming
Part 4:It’s up to readers to think and decide whether people should do something about global warming or not.Writing techniques
Using a question leaving readers to think over the issue
Giving examples using graphs, explanation
Raising a question
Giving examples, making contrastMatch the writing techniques with the correct partABDCABCDThe different ideas between Dr. Janice Foster & George Hambleygo upcatastropheVery seriouspositiveproducea greater range of animalsReading V DebateABA : We shall do something about global warming.B: We shall do nothing about global warming.
What's your opinion?SummarySkim over the passage, and tell what you have learnt in class. Try to talk in general terms rather than in details.
eg: I learnt that the earth is becoming warmer.
I learnt that global warming could have terrible effects on the environment.
….The animals’ fate is the human beings’ fate !
We must take measures to stop global warming !HomeworkRead the text after class over and over again and find the words or expressions you can’t understand.Good bye
