Letters serve many different purposes. They are broadly classified into two categories: social letters and business letters.
Write a letter to your uncle wishing him on his 70th birthday.
20th May, 2014
My dear uncle,
I just remembered that it is your birthday on Monday. Many happy returns of the day. I hope the day itself will be peaceful and joyous for you.
You have always been kind and generous to me and I take this opportunity to thank you from the bottom of my heart for all you have done for me.
I am so happy to hear from aunt that you are still hale and hearty. I am sending you a birthday gift which I think you will like.
I am getting on well in my career and expect to get a promotion this year.
With love and best wishes