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to become clear (water, air, etc.); to become transparent
to resonate clearly (e.g. voice)
to become serene; to become tranquil; to be free of worries
to pronounce as an unvoiced sound
彼の言葉で心が清んだ気がした。
His words made me feel at peace.
水が清んで川の底まで見える。
The water is clear and you can see the bottom.
雨上がりの空気が清んで遠くの山まで見えた。
The air cleared after the rain and I could see distant mountains.