Air is all around us. It is around us as we walk and play. From the time we were born air is around us on every side. When we sit down, it is around us. When we go to bed, air is also around us. We live in air. We can live without food or water for a few days, but we cannot live for more than a few minutes without air. We take in air. When we are working or running we need more air. When we are asleep, we need less air. We live in air, but we cannot see it. We can only feel it when it is moving. Moving air is called wind. How can we make air move? Here is one way. Hold an open book in front of your face, close it quickly. What can you feel? What you feel is air.
空气就在我们周围，在我们散步和玩耍的时候四处存在。从我们出生开始我们周围的空气无处不在。当我们坐下来，它在我们周围。当我们睡觉时，空气也在我们周围。我们生活在空气中。我们没有食物或水还可以生存几天，但我们没有空气就不能存活超过几分钟。我们吸进空气。当我们工作或跑步时我们需要更多的空气。当我们睡着了，我们需要较少的空气。我们生活在空气中，但我们看不见它。我们只能在它移动的时候感觉到它。流动的空气被称为风。我们怎样才能使空气流动？这是方法之一：在你的面前摊开一本书，快速合上它。你能看到什么？你感受到的就是空气。