English joke: swimmer, swimmer

The teacher told the class a story. A man swam in the river three times before breakfast.

Johnny smiled.

Do you doubt that an excellent swimmer can do it? The teacher asked.

no

sir

Johnny replied.

But I don't understand why he didn't swim four times and go back to where he put his clothes. swimmer

The teacher told the students a short story about a person who had to swim in the river three times before breakfast.

Johnny smiled.

The teacher asked, do you believe that swimming is good?

Johnny replied, no, sir, I don't understand why he didn't swim four times to get back to the side where the clothes were.

note:

I want to know ... which means I want to know. ...