Dear {Recipient}
Please allow me to apologize for what I {said, did, etc…} on {day of week}. My behavior was extremely inappropriate, immature, and lacked the respect {you, organization} deserved. It was a disruption and distracted others from {doing their job, learning, etc…}.
It was embarrassing, but I learned that nobody appreciated my poor behavior. In the future, I have every intention of curbing my thoughtless actions and learn to adjust my behavior befitting the environment and situation.
Again, I am sorry for my actions and I hope that we can put this matter behind us. I look forward to {working, learning from, etc…} you {again/soon}. If you have any thoughts in this, please feel free to share. You may contact me at your convenience at {email/phone}.
Sincerely,
{Sender Name}
