Dear ( Numele invitatului)

I would like to inform you that this Sunday I will have a party while my parents are on their trip. The party will be at ( ora la care se va da petrecerea) o'clock. 
 I bought  lots of food, there will be music, and  I also invited  my other friends too, many of them. It would be terrific to see you at my party too, it was a long time since  we last  hanged out, so this would be a nice way to have some fun together! I hope I'll see you on my party, and I hope you won't dissapoint me by not showing up! I'll be expecting  to see you on Sunday!

E bine formulata da?
Da, am incercat cat mai mult sa evit locurirle unde nu eram destul de sigur despre gramatica. Daca ai vrea, ti-l pot traduce in Romana.