Say you can't breathe with your mouth open and your tongue out. What's the joke?

This is an interesting joke. It can be said that:

When listening to a lecture, a person suddenly needs fresh air, so he decides to open his mouth and stick out his tongue. He quietly stuck out his tongue and tried to breathe through his nose, but soon found it useless.

The man sitting next to him saw this scene and asked him, "What's the matter with you? Why stick out your tongue? "

He replied, "I need some fresh air, but I don't want anyone to know."

The man sitting next to him smiled. "You can retract your tongue and breathe through your nose."

He said in surprise, "Really? Why didn't I think of that? "

The man sitting next to him replied, "Because you are so eager to breathe, you forget the most basic breathing method."

This is the origin of jokes, that is, when we are in a hurry to do something, we may forget the simplest method.