be minding your own businessto be doing something ordinary on your own when something unexpected happens to you 〔意外发生时〕正好好地做着自己的事 My father was just driving along, minding his own business, when suddenly a brick came through the window. 我父亲正好好地开着车,突然一块砖破窗而入。
be minding your own business• It's a bit disconcerting to be minding your own business.• I was minding my own business, sleeping, when I heard something.
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