In the heat of the sun, water evaporates from seas, rivers and lakes. As water vapour rises, clouds form in the air. When the clouds rise high, they get cool. Finally they become drops of water. When they are heavy enough, they fall to the earth as rain.

　　在太阳的照射下，水从大海、河流和湖泊上蒸发。当水蒸气上升时，云就在空中形成了。当云升高后，就变凉了，最后变成了一滴滴的水。当水变得足够重时，就作为雨水落到地面上。