The world is not hungry, but it is thirsty. It (seem) strange that nearly 3/4 of the earth is covered water while we say we are short of（短缺）water. Why? Because about 97% of water on the earth is sea water which we can't drink or (use) for watering plants directly（直接地）. Man can only drink and use the other 3% of the water that comes rivers and lakes. And we can't even use all of that, because some of it is (pollute).
Now more water is needed. The problem is: Can we avoid (避免) a serious water shortage later on? First, we should all learn how (save) water. Turn the tap off while (brush) your teeth, washing your hands, doing the dishes, and so on. Second, we should find the ways to reuse it. Scientists always make studies in the field. Today, in most large (city) water is used only once and then runs to the sea or rivers. But it can be used again. Even if(即使) every large city reused (it) water, still there would not be enough. From now on, everyone should save the water.
