How do you write please come back in Italian?

Answer 1

"Please come back" can have many different definitions and meanings, so it would depend on what you are writing about, and to who.

If you are writing informally, perhaps to a friend, and you're asking him to come back to, for example, your house, you could write, "Ritorna [a la mia casa], per favore." If this is formal, it would be "Si prega di ritornare (or restituirsi) [a la mia casa]"

If you are talking about responding to a letter, you could say, informally, "Rispondi, per favore" meaning "respond soon, please", or, formally, "Si prega di rispondere."

However, as I said, it really does depend on what you're writing about, and to whom.