increase in carbon dioxide.

The first graph shows the temperature increase of one degree Fahrenheit between 1860to 2000.

The second graph shows the carbon dioxide content in the atmosphere from 1957 to 1977.

4. What are the two graphs about?

The first graph shows the temperature increase of one degree Fahrenheit between 1860to 2000. The second graph shows the carbon dioxide content in the atmosphere from 1957 to 1977.

Step 3 Skimming

Read the passage carefully and judge whether the statements are true or false.

1. The temperature last century didn't increase much.

2. Everyone believes that global warming is caused by the activities of humans.

3. Janice Foster believes that global warming is caused b the burning fossil fuels.

4. Natural gas is a greenhouse gas.

6. People accept Charles Keeling's data because he took accurate measurements.

7. Flooding could be one of the effects of future global warming.

8. George Hambley believes scientists are just guessing about the effects of global

warming.

9. George Hambley is worried about the effects of carbon dioxide on plant growth.

10. It is clear what the effects of global warming will be.

Keys: True: 3, 5, 6, 7, and 8 False: 1, 2, 4, 9, 10

Step 4 Detailed reading

Read the text carefully and try to find out how many parts we can divide the text into and find out the main idea of each part.