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to throw into; to toss into
to throw-in; to play a throw-in
荷物をトランクに抛り込んで急いで出発した。
I tossed the luggage into the trunk and left in a hurry.
彼は手紙を封筒ごとゴミ箱に抛り込んだ。
He tossed the letter into the trash, envelope and all.
子どもが石を次々と川に抛り込んでいる。
A child is tossing stones into the river one after another.