Five Minutes to Midnight

A cop drives up to lovers lane and sees a car there. So he walks up to the car, and there's a girl in the back seat knitting and a boy in the front seat reading a book.

The cop asks the boy how old he is and what he's doing. The boy answers, "I'm reading a book and I'm 20."

Then the cop asks what the girl's doing and how oldshe is. The boy replies, "She's knitting and she'll be 18 in about five minutes."