1. I have already eaten the breakfast.
2. I haven't been to Italy yet, how is it?
3. Don't tell me you've seen this already!
4. We haven't bought a car yet.
5. I haven't finished writing yet.
6. Have you already spoken to your dad?
Moje odpowiedzi powinny być poprawne, ale polecam Ci je jeszcze samodzielnie przeanalizować :)