To enter a place forcefully, often to steal or damage.
The thief broke into the store to steal money.
泥棒が店に侵入してお金を盗んだ。
To interrupt something that is happening.
The loud noise broke into the quiet room.
大きな騒音が静かな部屋に割り込んだ。
To start using something new, especially after not using it for a while.
He broke in his new boots by hiking in the mountains.
彼は山間をハイキングすることで新しいブーツを着慣らした。