When people don't use their cars, they keep the cars in garages or parking lots. 人们不使用汽车时，会把车放在车库或停车场里。

　　Then where do people keep their ships? 那么人们把船放在哪里呢？

　　A harbor is the place. 放在港口。

　　Some harbors are naturally made and some harbors are built by people. 有些港口是天然的，有些港口是人工建造的。

　　A long time ago, ships were the major means of transportation, 很久以前，船舶是主要的交通工具，

　　so many people lived near harbors. 许多人住在港口附近。

　　That is why there are many old cities near harbors. 这就是为什么港口附近有许多老城市。

　　Can any area on the coast become a harbor? 海岸上的任何地区都能成为港口吗？

　　No, it can't. Because the water should be deep enough to put the anchor of a ship down. 不是的。因为水足够深，才可以把船锚抛下去。

　　There are many natural harbors around the world. 世界上有许多天然的港湾。