A professional letter can be written for any cases. For example, a professional letter can be used as an letter of recommendation or simply it can be used as an tool to express yourself to others. A professional letter template is given below.
Date of letter.
Subject:- Regarding Recommendation for Aishwarya
Dear Mr./Mrs. Name,
I am your name and designation, writing this letter of recommendation for [name of the candidate].
I know aishwarya for a period of three years and I am happy to write a recommendation letter for her. During her working days in our team, she was committed and dedicated in her duty and completed all works in time and was up to her level.
I can assure that aishwarya can surely meet your requirements and needs and can excel in her career with you.
Thanks and Regards,