In the lower reaches, where the current slows, the natural accumulation of sediment in the riverbed has caused the river to changecourse often in the past.
在河流下游,由于流速变缓,泥沙(等沉淀物)自然而然地堆积在河床中,曾经造成黄河经常改道。
2
Later it declined due to the changeof a rivercourse.