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to nod; to bow one's head in assent; to agree
彼女は私の提案に肯いて賛成の意を示した。
She nodded to my proposal and showed her approval.
先生の話を聞きながら肯く学生たちの姿が見えた。
I saw students nodding while listening to the teacher.
質問に対して彼は黙って肯いただけだったよ。
He just silently nodded in response to the question.