Of course he is still learning the construction. I've tried to explain the maxim articulated in Woody Allen's Crimes and Misdemeanors: "If it bends, it's comedy. But if it breaks..."
Sometimes his efforts at jokes are sound like a joint effort between Henny Youngman and Lawrence Ferlingheti. Just the other day he tried one on me:
Why did the chicken cross the road?But sometimes he gets it just right.
To fix the tractor.
One of his jobs is to get my newspapers in the morning (I get three - I don't exactly read them, I just get them). Usually he doesn't "feel like it" and I've fired him a dozen times. But this morning he hauled them in and said, "Daddy, you need to get two more papers."
"Ugh, why? When would I read them?"
"C'mon Daddy, you can never refuse a fifth!"