Bobby is driving and suddenly sees a tree in the middle of the road. He quickly swerves and just misses it. But then he sees another tree and another. As soon as he swerves past one, he sees another.
Finally a police officer pulls him over and asks why he keeps swerving in the road.
“I’m just trying to miss the trees in the middle of the road!” Bobby replies.
“Oh,” the policeman says. “That’s your air freshener!”