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- “Teaching fish to swim” 9 answers
I am looking for an idiom/phrase which would mean that someone is trying to explain something to someone who obviously knows how it's done. It would be like a maths student trying to teach/explain to his maths professor in his university how to do calculus - he clearly knows it better than you!
My language has for example "nie ucz ojca dzieci robić" - that translates as "don't teach a father how to make kids" - is there an equivalent in English?