陵谷变迁

Explanation: Ling: Datu Hill; valley: narrow lane between two mountains. Hills become valleys and valleys become hills. Metaphor things change, compete translocation. 　　Source: "Book of Songs Xiaoya October at the turn of" Takagishi the valley, deep valley for the hills. " 　　Examples: Later "~", which in the vicinity of the terrain elevation, river diversions, it becomes a dry Kawadani. (Yao Xueyin "Rereading" five chapters of volume II)