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to refuse; to reject; to dismiss; to turn down; to decline
to inform; to give notice; to ask in advance (and get approval); to get permission
to ask leave; to excuse oneself (from)
友達の誘いを丁寧に断わった。
I politely turned down my friend's invitation.
無理な頼みは断わるべきだと思う。
I think you should refuse unreasonable requests.
彼は申し出を断わる勇気がある。
He has the courage to refuse the offer.