Hello,
Construction plus que parfait → Had + participe passé
1. I went to Paris two days ago.I had already been to Europe several years before.
2. I ate the apple I had bought in the supermarket.
3. Had you done your homework when your friend arrived?
> Réponse: Yes,I had.
> Réponse: No, I hadn't.
En espérant t'avoir aidé(e) ! ^^