Respected Sir/ Madam,
I would like to inform you that I, ________ (Your Name) working in __________ (department) have completed my pending _________ (work/projects) as a _______ (designation), and I am writing this email to request you to grant me a sabbatical from _______ (date) for my _________ (reason for sabbatical leave).
I will be able to rejoin on _________ (joining date).
I will be available on email _________ and can even contact me on _________ during my leave. I hope you will consider my request and provide me with your support.
Thank you in advance.
____________ (Contact details)