Sir/Madam,
I, __________ (name) working as ___________ (designation) in your reputed company i.e. ___________ (company name) and my employee ID is ____________ (employee ID).
I am writing this email in order to bring into your kind consideration that I am not feeling well and due to which I will not be able to come office for __________ (number of days) days. This is to request you to kindly approve my sick leave from __/__/_____ (date) till __/__/_____ (date) and I shall be highly obliged for your kind support.
This is to request you to kindly look into the same and respond at the earliest.
Thanking you,
____________ (Name),
____________ (Employee ID number)