CALLING ALL CURIOUS PEOPLE: THE REASON WHY WE YAWN, AND WHY IT IS CONTAGEOUS.
IT IS DUE TO HUMAN INSTICT. IT IS THE MOTION OF OPENING YOUR MOUTH WIDE. WE DON'T REALISE WHY WE DO IT, BUT IT'S NATURAL.ITS A MIRROR NEURON REACTION. ITS THE UNCONSIOUS PART OF OUR BRAIN KICKING IN. THE REASON WHY PEOPLE YAWN IS BECAUSE SOMETIMES WITHOUT 你 KNOWING, YOUR LUNGS GET LAZY AND DONT TAKE IN ENOUGH AIR, PARTICULARLY WHEN YOUR TIRED. SO, THE YAWN TOPS 你 BACK UP AGAIN. WHEN YOU'RE BORED 你 DONT TAKE IN AS MUCH AIR AS 你 SHOULD, SO YOUR BREATHING SLOWS DOWN THEN, TOO. THAT IS WHY PEOPLE YAWN, AND WHAT IT MEANS.
it depends on if 你 have an emotional connection with the person who previously yawned. if 你 do, something in your brain sorta triggers and 你 yawn, almost like youre answering their call 或者 something like that.
Yawns are caused 由 too much carbon dioxide in the lungs. Seeing someone yawn, 或者 thinking about yawning (I'm yawning right now) I think makes 你 remember that you're breathing. Once 你 realise that, it can sometimes become harder to breath. ...To be honest, I have no idea what I'm 写作 here, I'm just putting up some 随意 stuff that sounds vaguely scientific.