Dear Jenny
How's it going?I didn't see you for a long time,I miss you so much.
You know,my birthday will come,so I determine to hold a birthday party on this Friday afternoon.
I‘m writing to inform you to join my birthday party.It wold be a great pleasure to me if you can come.
Please give me a call if you can come. I'm at home in the evening. Looking forward to seeing you.
Yours
XX