No matter how old you get, your teachers will always be more grown up than you. Last night I went to a cocktail party hosted by the headmaster of my high school. He was in Boston with some other faculty and staff and invited a bunch of alums to a gathering.
One of my former teachers was there, and he looked exactly the same as when I was in school. Hasn't aged a day. And even though I've been out of high school long enough to call him by his first name, I just couldn't. It just felt too weird, like he could send me to the head master's office or call my parents or something.