talk about greenhouse gases. Have you heard about this before?

T: That's correct. Then what do you think greenhouse gases do?

Sd: Let me explain it. They trap heat from the sun and therefore warm the earth.

T: Yes. Last class we talked about the effects of burning fossil fuels. One of the effects is more and more carbon dioxide is being produced, which in turn increases the speed of global warming. Does it matter? What're your opinions? Next we'll read an article "THE EARTH IS BECOMING WARMER - BUT DOES IT MATTER?"

Step Ⅲ While-reading

Get the students to read the passage fast and meanwhile help the students form a good habit of reading.

T: What do you think will be talked about at the sight of the title "THE EARTH IS BECOMING WARMER - BUT DOES IT MATTER?" Now please skim the passage to obtain a general idea of the whole passage. While reading, pay attention to the writing skills and if possible, divide the whole passage into several parts and summarize the main idea for each part.

After a few minutes.

T: How many parts can this text be divided into?

T: Any different ideas? OK. Now let's finish the form on the screen.

Show the form on the screen and let the students complete the form.

Let the students read the passage again to find out the answers to the questions in Exercises 1 and 2.