Topic 1 1 What is renewable energy? Give some examples. 2 What is non-renewable energy? Give some examples. Topic 2 1 Which hour are rush hours in your community? 2 Why should we travel by public transport instead of private transport? 3 What difficulties do you meet when you are stuck in a traffic jam? 4 What means of transport do you think will be used in the future? Topic 3 1 Give four problems of overpopulation 2 Give measures to solve these problems