Little Johnny came home after school:
“Daddy, I have a bad grade in English language. “
“Why?” asked his father.
“Well, the teacher asked us the following question: “Mary entered the forest with John and came out of the forest with Mike. What is Mary?”
“How come what Mary is? A whore, of course, “said the father.
“That’s what I said, but the teacher answered Mary was a subject. “
This joke is included in the Black Book of Jokes. You can order it from here.