A man in a restaurant was giving the waiter a lot of trouble. First, he felt it too hot, so he asked the waiter: "Excuse me, could you turn on the air conditioner (空调) It’s too hot here that I can’t bear any more!" Then a few minutes later he asked the waiter again: "Excuse me! Now it’s too cold! Would you turn it off!" Several minutes later he felt hot again, and he let the waiter come and asked him to turn on the air conditioner again. This went on for about half an hour. However, although the customer was so annoying, the waiter was very kind. He did everything the man asked without getting angry. Finally, someone else in the restaurant could no longer bear it. He couldn’t help asking why the waiter didn’t just throw the annoying man out. And you know what the waiter said The waiter said, smiling: "Oh, I don’t care because we don’t even have an air conditioner.\ Because the customer was ill, he felt sometimes hot and sometimes cold.