[{"role": "user", "content": "I am reading a historical text and came across the sentence 'They retreated.' I'm curious to know how to express this idea in Italian."}, {"role": "assistant", "content": "That's a great question! The correct translation of 'They retreated' in Italian is 'Si sono ritirati.' This sentence is in the passato prossimo tense, which is used to describe completed actions in the past."}]