Here are some common mistakes to avoid when using passive voice in Italian:

1. Verb Agreement: Always make sure the past participle matches the subject’s gender and number.
   For example:

   • "Le lettere sono scritte" (the letters are written)
   • "Il libro è scritto" (the book is written)

2. Overusing Passive Voice: Sometimes, it's better to use active voice to make your writing more lively. Don't hesitate to change things up!

3. Incorrect Prepositions: Make sure to use the right preposition, like “da” when talking about who did the action.
   For example:

   • "È stato scritto da Maria" (It was written by Maria).

Remember, practice helps you improve!