VIII: Give the correct forms of the words in the brackets.
1. Many people are very concerned about the (destroy).......................of the rainforests.
2. The air in the city is heavily (pollute).......................with traffic fumes.
3. The local residents promise to keep the environment (clean).......................
4. Our teacher is pleased that we solved the problems (effect)...........................
1 destruction
2 polluted
3 clean
4 effectively