Jimy Ortan,
1234, West 67 Street,
Carlisle, MA 01741,
(123)-456 7890.
[Subject: Normally bold, summarizes the intention of the letter] -Optional-
Dear Jimy Ortan,
I am enclosing a check for payment for 3 months that I owe to you. Due to unfortunate circumstances I lost the job, and am now on a new job hunt. Therefore I have not been able to pay your full rent on time. I really hope it has not troubled you, and I shall make it a point to be better from the coming times.
Sincerely,
Kessie