As we know , water is very important to man, we can’t live without water. The amount of water
which is suitable to drink is less and less. But some people don’t care about it .They waste a
lot of water in their daily life. Even worse, they pour dirty water in to rivers. They throw rubbish into rivers , too. Many rivers and lakes are seriously polluted.Something must be done to stop the pollution. Only in this way can we live happily. If we don’t save water, the last drop of water will be a tear-drop of us. People can’t imagine life without water. Without it, the earth we live on would be a dead one. There would be no trees, no crops, no animals and no people.Although nearly three quarters of the earth’s surface is covered with water, it is sea water and undrinkable. The demand for water is increasing, while water resources are scarce. So water shortage has become one of the most serious problems.Fortunately, people have realized this pressing problem and are trying to find ways to salve it. First, people are urged to economize on water. Second, measures are taken to protect water resources. Third, circulating water is used for industrial purposes over and over in factovies and treated sewage water is used for irrigation in farming land. We know that despite the fact that seventy percent of the earth＇s surface is covered with water, only a little part of it is fresh water. Yet the demand for fresh water in our daily life and in industry seems great. Moreover, with the expansion of the population and development of industry, the amount of the fresh water needed will increase even rapidly. It is estimated that if such a trend continues, the fresh water on earth will be exhausted very soon. What is worse, more and more water resources are being polluted, making the water unfit to use. In addition,We must warn the people of the importance of water and the danger are facing.For example, in most Asian societies where rice is the staple food, the water used after cleaning rice contains various nutrients for plant growth and is an excellent detergent to flush the toilet. Furthermore, the intriguing idea of converting the inexhaustible sea water to fresh water supplies will be the ultimate solution.