[{"role": "user", "content": "I'm trying to learn Italian and I'm stuck on the sentence 'He lost a book'. Can you help me translate it?"}, {"role": "assistant", "content": "Certo! The translation of 'He lost a book' in Italian is 'Lui ha perso un libro'."}, {"role": "user", "content": "That's really helpful, thank you. What if I want to say 'He lost a book' in a more formal way?"}, {"role": "assistant", "content": "In a more formal context, you could say 'Egli ha perso un libro'. However, 'Lui ha perso un libro' is also widely accepted and used in formal conversations."}]