Mr. Jones moved to another town, and soon he needed a new doctor, so he went to see one. He sat down in the waiting room and looked around. The doctor´s degrees were on the wall. Suddenly Mr. Jones remembered there had been a student with the same name in his class at school, and he had become a doctor!
He went in to see the doctor, remembering a young, handsome student, and was sad to see how old and heavy and grey this man looked. However, he said to him "Good morning, Doctor. Did you go to Middletown High School?"
The doctor answered "Yes, I did."
"Were you there from 1970 to 1974?" Mr. Jones asked.
"Yes, I was", the doctor answered. "How did you know?"
Mr Jones laughed and said, "You were in my class!"
"Oh?" the doctor said, looking at him carefully for a few moments. "What were you teaching?"
L.A.Hill. Intermediate anecdotes in American English. Oxford University Press