1) Yawning is a part of our life.
2) A person often does not notice how yawns.
3) People yawn not only when they are tired.
4) The average yawn lasts 5-6 seconds.
5) Yawn control the brain.
6) You begin to yawn even in the womb of the mother.
7) Yawning is contagious, if someone yawns next to you, then it is likely that you are yawning too.
8) Animals also yawn.
9) A man yawns from the fact that he lacks oxygen.