Write a letter to your Maternal Uncle telling him why you intend to join a computer course. 

130 R. Model Town, 

Sonipat. 

28th Nov., 20…..

Respected Uncle, 

I trust that this letter finds you in the best of your health. As I have passed my Secondary School Examination with distinction marks, now I want to join the Computer Course. My friend has a great acquaintance with this technique. The promotional avenues are also very bright in this course. It is on the advancing stage. The day is not far when every office will be filled with a computer. In all Government as well as private concerns, computers are seen working. They guide and supervise the work. It is going to become an essential item. So the trained personnel in the computer will be required in every field whether in Public Sector or in Private Sector. 

In view of the above, I hope you will allow me to join the computer course. Though you will have to incur extra expenditure. Pay my best regards to my respected Aunt. 

Yours affectionately, 

Vikas