Water always flows from a higher place to a lower place rivers and lakes are deep valleys on the earth. The snow water and spring rain water from the mountins rain water and ground water all flow into the deep valleys. Gradually， the deep valleys become rivers. When the small ditches¹ gather together. They become small river； and several small rivers will become a big one. When spring water rain and snow water from all directions join， they form a river or a lake.

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