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expression; look; countenance; face
緊張した面持ちで試験に臨んだ。
I took the exam with a tense expression.
穏やかな面持ちで話を聞いていた。
She was listening with a calm expression.
真剣な面持ちの医師から検査結果を聞いた。
I heard the test results from the doctor, who had a serious expression.