Your father has sent you a present of five hundred rupees on your birthday. Write a letter of thanks to him, tell him how you propose to spend the money. 

Dear Father, 
What a splendid present you have sent! Five hundred rupees! Thank you very much indeed for having made me such a generous gift. 

Five hundred rupees! It means a great deal to me. Now I shall be able to all the books I have seen desiring for some time. 

I propose to buy all the five books written by P.C. Wren. These books are very useful. They are matchless. My Chemistry teacher Mr. Goel has advised me to study them. Beside these books I need the concise Oxford Dictionary and Father Kamil Wolke's Dictionary (English to Hindi) published by S. Chand and Company, Delhi. 

Hoping that you are in, the best of your health and with renewed your thanks for the splendid present. 
I am, dear Father. 

Your loving son, 
Mukesh