Ex3: Write conditional sentences type 2, using the cues given. 1. If/ we/ destroy/ the ozone layer/ what/ save/ us/ the UV rays? 2. If/ people/ not really care/ the environment/ they/ not try/ save it. 3. The river/ not be/ so polluted/ if/ factories/ not dump/ waste/ it. 4. We/ be/ less worried/ if/ oil spills/ not have/ such destructive effects. Ex4: Complete the sentences with the correct form of the verbs in brackets. (Dùng dạng đúng của ĐT trong ngoặc: theo công thức câu ĐK 1 hoặc 2) 1. If we_____ (not recycle) paper now, we’ll need to cut down more trees in the future. 2. If the local people_____ (have) fresh water, they wouldn’t have to use polluted water. 3. What________ (happen) if radioactive material was not handled properly? 4. If we recycle more household waste, there____ (be) less damage to the environment. 5. If we________ (not understand) environmental problems, we would not be able to do anything about them. 6. If the polar ice-caps melted completely, Sea levels worldwide_ (rise) about 60 metres. 7. The amount of plastic in the ocean________ (increase) if we________ (not take) action now. 8. These fish_____ (not die) if the factory ____ (not dump) its toxic waste into the river. 9. There ________ (not be) enough oxygen if we ________ (not protect) the rainforests. 10. If I ________ (be) the President, I ________ (ban) billboards in cities in order to reduce visual pollution.