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to jump in; to leap in; to plunge into; to dive
to burst in; to barge in
子供たちが川に飛込んで遊んでいた。
The children were playing by jumping into the river.
急いでタクシーに飛込んで駅に向かった。
I jumped into a taxi and headed for the station.
鳥が巣に飛込む姿を写真に撮った。
I took a photo of the bird diving into its nest.