From the brain a long white cord, called the spinal cord, goes down through the backbone. 从大脑开始, 一根长长的白色索状结构通过脊柱向下延伸, 这就是脊髓。

　　A great number of fine white threads, called nerves, run from the brain and the spinal cord to all parts of our body. 另外还有很多白色的线状结构从大脑与脊髓通往身体的各个角落, 这些便是神经。

　　There are so many of these nerves, that we cannot prick our skin without touching one of them. 神经的数量太过众多, 无论我们刺到哪里的皮肤都能够感受到它们的存在。

　　We know this because we cannot prick the skin without feeling pain. 之所以如此是因为, 只要刺一下皮肤, 肯定就会感觉到疼痛。

　　The nerves act very much like telegraph wires, for they carry messages to the brain which make us feel, and see, and hear. 神经与电报线的运作原理相似：它们能够向大脑传递信息, 从而让我们感觉、看到、听到周围的世界。

　　They also carry orders from the brain to the muscles, which make them contract and relax, and thus our limbs are made to move as we wish. 它们还能够向肌肉传达来自大脑的指令, 让它们收缩与伸展。如此一来, 我们的四肢便可以根据我们的想法进行运动。

　　There are many other organs in the body, every one of which has some work to do in keeping us alive and well. 人体里还有很多其他器官, 它们各有分工, 确保我们的生命与健康。

　　All the organs work together, and they work so quietly when the body is in good health, that we do not know 所有的身体器官相互配合。当身体健康时, 它们发挥自己的职能时无声无息,

　　except, perhaps, by the beating of the heart—that they are in our body at all. 除了心跳之外, 我们几乎感觉不到它们就在我们的身体之中。

　　But if we eat too much, or if we drink too much, 然而, 如果我们暴饮暴食，

　　and especially if we drink wine, beer, and spirits, which contain a substance called alcohol that acts like a poison when taken in excess 特别是喝了葡萄酒、啤酒与白酒这些含有酒精的物质时（过量饮用酒精便可中毒）

　　then our organs cannot work properly, and we feel ill. 我们的身体器官就无法正常工作, 我们也就病倒了。

　　The body needs proper food, and fresh air, and plenty of exercise to keep it in good order. 人体需要适当的食物、新鲜的空气以及充分的锻炼, 这样才能保持健康。