BREAK A LEG

broke a bone in his lower leg; was successful

good luck! (often said to actors before a performance)

"Break a leg" is a well-known saying in theatre which means "good luck". It is typically said to actors before they go out onto stage to perform.The expression is a theatrical superstition that replaces the phrase "good luck," which is considered bad luck. The expression is sometimes used outside the theatre as superstitions and customs travel through other professions and then into common use.
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good luck, have a good performance """Break a leg!"" she whispered as he walked on the stage."

Good luck!

BUONA FORTUNA! [GERGO TEATRALE]