I once read a joke to the effect that as soon as a person learned to ride a bike, he rode on the road. He saw a man and shouted stop, so he hit that man.

A man has just learned to ride a bike. He was riding on the road when he suddenly saw a man in front. He was frightened and shouted, stop! The person in front stopped quickly and was knocked down with a bang. ...

The man got up from the ground and said, you told me to stop, so you can aim, right?