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in a lively way; vividly; freshly; animatedly; actively; energetically
子供たちが生き生きと遊んでいる。
The children are playing in a lively manner.
彼女の目が生き生きと輝いていた。
Her eyes were shining vividly.
生き生きとした表情で話していた。
He was speaking with a lively expression.