Lets say your friend's name is sarah..
{Insert address},
{Insert date}.
Dear Sarah,
I hope you are in good health. I am happy to inform you that this year I will be celebrating my birthday with all my friends. You are cordially invited to my birthday party.
Due to exams in the last few years, I was unable to have a birthday party. But this year as all of our exams are finished, my parents decided to throw me a birthday party.
You are one of my closest friends and I cannot have my birthday party without you. We will have different flavoured chocolates and ice creams for everyone. I have also planned a unique return gift for all my friends. The party will begin at {insert time that party will start} at our home on {insert date the party is on}.
I will be eagerly waiting for you.
See you soon,
{Insert your name}
