The earth is our home. We must take care of it for ourselves and for the future generations. The importance of this task is great as scientists who study the relation of man to nature say. These scientists are called “ecologists”, from the Greek word “oikos”, which means home. Ecologists are trying to keep the land, air and water clean. Why must we keep our earth clean? We have only a certain amount of fresh water and clean air and we must take care of it. If we don’t stop air and water pollution, trees and flowers won’t grow, fish will die in dirty water. We will have to breathe dirty air. Of course, people are working to make the earth cleaner, but they must do more. What can people do to make earth cleaner? Factories must stop polluting air, rivers and lakes with waste products and chemicals. They must work on it more. Lakes and rivers must be cleaned and kept clean. Environmental problems concern everyone. We should remember that everyone can do something to solve them. We all want to live in a clean world.