Ask more pairs to give their answers, having one student read out the question and another answer it.

　　Suggested answers:

　　1 The climate.

　　2 New York and Shanghai.

　　3 Because pollution is stopping the sun's heat leaving the atmosphere.

　　4 Carbon dioxide from cars.

　　5 There is less oxygen and more carbon dioxide in the atmosphere.

　　6 Optimistic.

　　4. In Activity 4, ask students to read through the sentences and try to anticipate what the missing words might be.

　　1 As a result, the ice at_____________ is beginning to melt.

　　2 The sea may rise and cities on the coast may_____________ .

　　3 Too much carbon dioxide pollutes the_____________ .

　　4 Trees take in_____________ and give out_____________ .

　　5 We_____________ garbage and pollute the atmosphere.

　　6 Instead, we should_____________ the garbage.

　　Then play the tape for them to complete the sentences individually.

　　If necessary, play the tape again, isolating any problem sections for intensive listening.

　　Suggested answers:

　　1 the Poles　2 disappear(under water)　3 atmosphere　4 carbon dioxide, oxygen　5 burn　6 recycle

　　→ Step 3 Speaking 2

　　1. Turn to Page 37, and have a look at Speaking 2.

　　First, ask students to repeat the words in the boxes.

Coal　plastic　refrigerators(fridges)　cars　cutting down trees 　　Pay attention to word "refrigerators" where the stress is on the second syllable.

　　Then pair students to talk about the problems they caused.

　　damage　give out　environment　carbon dioxide　chemicals　pollute 　　Before the discussion, the teacher can ask questions, such as

　　1. When "coal" and "plastic" are burned, what results will they cause?

　　2. If you cut down too many trees, what may happen?

　　If students are not clear about the problems, then initiate a class discussion and list them on the blackboard. (If possible, use multimedia. )

　　coal smoke pollutes, plastic doesn't biodegrade easily, fridges contain CFCs which destroy ozone, cars emit carbon dioxide which pollutes, cutting down trees causes desertification and reduces oxygen while increasing carbon dioxide.

　　We have already known that things in the box are harmful to environment.

　　But how can we improve it?

　　Now think of ten things we need to do to improve the environment.

　　Work in pairs and exchange information with each other.

　　The teacher can walk around the classroom to monitor and help students.

　　Several minutes later, ask some pairs to read out their measures and the reasons.

→ Step 4 Summary and Homework