Would you please tell an interesting joke?

There is a mental hospital with few doctors and many patients, that is, there is only one doctor, but there are several patients, so the doctor thought of a good way, that is, choose a building director for each floor.

The doctor went to the first floor, took an insole and asked, "What is this?" One of them shouted "insole". Dean thinks he's ok, just say you're the head of the first floor.

The doctor went to the second floor, took a shoelace and asked, "What is this?" One of them shouted, "shoelaces". The dean thought he was better than others, so he said; You are the director on the second floor.

The doctor went to the third floor and got one. You ask, "Hey, what's the name of the one wearing shoes?" (At this time, people who listen to your jokes will definitely say "This is a shoehorn"), and then you will succeed and say "Haha, you are the director of the third floor!"