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quiet and subdued in appearance; solemn; sad and depressed in manner; soft; gentle
しめやかな雰囲気の中で式が行われた。
The ceremony was held in a solemn atmosphere.
雨の日はしめやかな気持ちになる。
On rainy days, I feel quiet and subdued.
しめやかに故人を偲んだ。
We quietly remembered the deceased.