How can I write an application for leave in advance ?

Write an application to your Headmaster of your school for advance leave mentioning the beginning and ending date of your leave. September 28, 2013 The Headmaster Charbairabi High School Haimchar, Chandpur Subject: An application for leave in advance Sir, With due respect, I beg to say that the marriage ceremony of my elder sister comes on next Monday, the 5th October. So, I shall not be able to attend the school from the 4th October to the 8th October 2013. May I , therefore, hope that you would be so kind as to grant me leave for those days only. I remain Sir Your most obedient pupil Md. Nasir Uddin Class- Roll- Section-