Bonjour, je te donne un exemple :
Dear (nom du destinataire),
I thank you for the beautiful birthday gift you sent me. Indeed, I was surprised! You gave me the birthday present I wanted the most, a new console (nouvelle console de jeux vidéos). I can't wait to play it with you and my friends, we'll have so much fun. Of course, I'll make sure to give you a better gift on your next birthday. It'll be better than last time, I promise. Anyway, I thank you once more for the present, and will play with you soon.
Have a great day!
(nom de la personne rédigeant la lettre)
J'espère t'avoir aidé(e). Bonne journée. :)
