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to cut into (a line, conversation, etc.); to force oneself into (e.g. a crowd); to wedge oneself into; to squeeze oneself into; to intrude on; to interrupt
to fall below (of stock prices, sales, etc.); to drop below
列に割り込む行為はどこの国でも嫌われる。
Cutting in line is disliked in any country.
男が突然列の前に割り込んだ。
A man suddenly cut to the front of the line.
誰かが私たちの会話に割り込んでいる。
Someone is cutting into our conversation.