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tummy; tumtum
bang-bang; pop-pop; tap-tap
without reservation; unreservedly; snappishly; outspokenly
one after another; successively
子供がお腹をぽんぽんと叩いた。
The child patted their tummy.
食べすぎてぽんぽんが痛い。
I ate too much, my tummy hurts.
赤ちゃんのぽんぽんを撫でた。
I rubbed the baby's tummy.