Today’s grammatical expression can be used when talking to a person who is being hypocritical. That means that the person says one thing but then does the opposite thing, or if a person criticizes another person for something that is also true of them. The expression is “look who’s talking”. It is used as a way to point out to the person who is being hypocritical that they are not doing what they say others should do. For example:
A: You’ve certainly gotten heavy recently. You should go on a diet.
B: You think I’m fat!? Look who’s talking! You must be at least 100 kg!
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A: I think you should stop smoking so much.
B: Look who’s talking! You smoke a lot more than I do!
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A: It would be good for you to exercise more.
B: Oh really? Look who’s talking! You never exercise!
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A: I think you’re too negative!
B: Are you kidding me!? Look who’s talking! You’re the most negative person I know!
So, as you can see, we use this expression as a response to another person’s comment about us when they are being a hypocrite. Generally, we only use this expression with people we know well and are close to. It’s a little too strong to use this with people we don’t know well.
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