Once, there was a very well-known school in the middle of a city. On the last day of school before the summer holiday, the students took a test. All of them passed but one. The teacher talked to the little boy afterword. “How did you get such a bad score? ” he asked.
The boy responded, “I did not understand the material.”
The teacher told him, “You could have asked a question. There were many opportunities.”
“I was afraid that I would ask a stupid question.” The boy answered.
The only stupid question is the one not asked.