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annual tree ring; growth ring
experience in life
切り倒した木の年輪を数えて樹齢を調べた。
I counted the tree rings of the felled tree to determine its age.
人生の年輪を重ねて深みのある人になった。
By accumulating life experience, he became a person of depth.
年輪を見ると気候の変化がわかるそうだ。
It is said that you can see climate changes from tree rings.