look who's talking

Từ điển Oxford Advanced Learner 8th

look who's ˈtalking | ˈyou can/can't talk | you're a ˈfine one to talk idiom
(informal)used to tell sb that they should not criticize sb else for sth because they do the same things too
•‘George is so careless with money.’ ‘Look who's talking!’
Main entry: ↑talk_idiom