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to clear; to make clear
to be unruffled; to look unconcerned; to feign indifference
to look demure; to look prim; to put on airs
to strain (one's ears); to listen carefully
濁った酒を布で澄ませて透明にした。
The cloudy sake was clarified through cloth to make it clear.
彼女は何事もなかったかのように澄ました顔をした。
She put on a composed face as if nothing had happened.
森の中で耳を澄ますと小鳥のさえずりが聞こえた。
When I strained my ears in the forest, I could hear birds singing.