Respected Sir/ Madam,
My name is ______ (name) and I am working as a _______ (designation) having ______ (employee code).
This email is to inform you that I am preparing for _____ (examination) and the date of the examination has been disclosed to be __/__/____ (date). I sincerely request you to sanction me study leave from __/__/____(date) to __/__/____(date). I assure you that I will work hard in order to qualify for the exam.
I hope that you will consider my request and approve the same. If you need any further information regarding the same, please let me know at the earliest.
__________ (Contact details)