【制度创新】

材料一：今大道既隐，天下为家。各亲其亲，各子其子，货力为己……

材料二：（周）王追思先圣王，乃褒封神农之后于焦，黄帝之后于祝，帝尧之后于蓟……封尚父于营丘，曰齐；封弟周公旦于曲阜，曰鲁……余各以次受封。

——《史记·周本纪》

Skin-diving(潜水) is a new sport today. This sport takes you into a wonderful new world. It is like a visit to the moon. When you are under water, it is easy for you to climb big rocks, because you are no longer heavy.
Here, under water, everything is blue and green. During the day, there is lots of light. When fish swim nearby, you can catch them with your hands.
When you have tank (罐) of air on your back, you can stay in deep of water for a long time. But you must be careful when you dive into deep water.
To catch fish is one of the most interesting parts of this sport. Besides, there are more uses for skin-diving. You can clean ships without taking them out of the water. You can get many things from the deep sea.
Now you see that skin-diving is both useful and interesting.