根据短文内容回答问题。

Water is very important to people. We must drink water every day. We can't live without water. Water is everywhere around us. At home, we use water to wash clothes, to wash dishes, to cook meals, to clean the flat, to have showers, to make drinks, to clean our teeth, to have a bath and so on. At work, people use water to put out fires, to grow vegetables, to make things in factories and so on. We also can swim on the earth. Water is important to us, isn't it?

However, there isn't much water on the earth. It is very valuable. We must save it. If we waste too much water, one day in the future, the last drop of water on the planet will be our tear.