No air means¹ death. Although we can't see it, there is air round us.So air is everywhere and it gives life to every living thing. Without it we can't live. Bad air makes people ill.We must have fresh air to keep ushealthy.

In the city there are a great many people and there are too many cars running on the roads. The gas which the cars spread out is full of poison². Every day we breathe it in and out.

Besides so many cars, there are many factories too.From the chimneys³ of these factories, we get the smoke usually in a black or grey color. This kind of smoke, when it mixes with the air, is dangerous to our health. It is because smoke contains many small poisonous soils and gases. So in

order to keep healthy we have to go out to the countryside to breathe more fresh air. Or we can go up hills to get more fresh air.

新鲜空气的重要性

没有空气就意味着死亡。 虽然我们看不到，但我们周围存在着空气。所以空气遍布各处，把生命带给每种生物。没有空气我们没法生存。空气不好使人生病。我们必须有新鲜空气才能保持健康。

城市中人口众多，路上跑着许多汽车。汽车排放的气体充满了毒害;每天我们吸进呼出这些空气。

除了有这么多汽车，还有很多工厂。从这些工厂的烟囱里，我们得到的通常是黑色或灰色的烟雾。这种烟雾一旦和空气混合，就对我们的健康产生危险。这是因为烟雾中含有许多小的有毒的颗粒和气体。所以为了保持健康我们就不得不到乡下去呼吸更多的新鲜空气。或者我们也可以爬山去呼吸更多的新鲜空气。