[Your letterhead, if desired; if not, your return address]
[Date of letter-month, day, and year]
[Recipient's first and last names]
[Street or P.O. box address]
[City, State ZIP code]
Dear [recipient's name]:
Can you believe that Anne is turning 30 next month? It's true, and a few of us want to get together for some fun-filled times in celebration of this milestone.
Please join us on Saturday, February 25, for a special dinner at Joe's house from 7 to 10 p.m. Gifts are optional, and your presence is most important.
Contact Joe at 555-1212 to let him know whether you'll be able to attend. He can give you more details on plans.
Hoping to see you for Anne's big 3-0 party!
[Sender's first and last names]