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lingering attachment; lingering affection; regret; reluctance; ruefulness
別れて一年経つが彼女への未練をいまだ断ち切れない。
I cannot cut off my lingering attachment to her.
過去に未練を持っても仕方がない。
It's no use having lingering attachments to the past.
未練がましいことは言いたくない。
I don't want to say anything that shows lingering regret.