The course changes frequently, and the area is so flat that a small change in the level of the river may inundate a considerable area.
河道变化多端，下游地区却很平坦，水位少许上涨河流就会淹没一大片土地。
The course changes frequently, and the area is so flat that a small change in the level of the river may inundate a considerable area.
河道变化多端，下游地区却很平坦，水位少许上涨河流就会淹没一大片土地。
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