Ex6: Combine each pair of sentences to make a conditional sentence type 1 or type 2. 1.Students are more aware of protecting the environment. Teachers teach environmental issues at school. If ……………………………………………………………………… 2.Light pollution happens. Animals change their behaviour patterns. If ……………………………………………………………………… 3.The levels of radioactive polluion decrease.We switch from nuclear power to renewable energy sources. If …………………………………………………………………… 4There are so many billboards in our city. People can not enjoy the view. If …………………………………………………………………… 5.There is so much light in the cityat night.We can not see the stars clearly. If ………………………………………………………………… 6.We turn on the heater all the time. We have to pay three million dong for electricity a month. If ………………………………………………………………