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alternately; in succession
嬉しさと寂しさがこもごも込み上げた。
Happiness and loneliness welled up alternately.
賛成と反対の意見がこもごも出された。
Opinions for and against were raised in turn.
光と影がこもごも差し込む森を歩いた。
I walked through a forest where light and shadow alternated.