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to warm (up); to heat (up)
to sit on (an idea, plan, etc.); to keep to oneself; to nurse; to mull over
to renew (an old friendship)
to take for oneself
朝食の冷めた食事を電子レンジで暖めた。
I warmed up the cold meal.
部屋を暖めるためにストーブをつけた。
I turned on the heater to warm the room.
心を暖める言葉をかけてくれた。
He said words that warmed my heart.