滄海桑田 [ㄘㄤ ㄏㄞˇ ㄙㄤ ㄊㄧㄢˊ; cang1 hai3 sang1 tian2]
  lit. the blue sea turned into mulberry fields (idiom)
  fig. the transformations of the world
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  滄海桑田
  そうかいそうでん
  Expressions (phrases, clauses, etc.)
  The word is a scene of constant changes (as the blue sea changing into a mulberry field). (Chinese legend)
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