I am still learning the NFL rules because they keep update them though I have watched football for a long time. This year they introduced a new rule called Horsecollar: any player is prohibited to grab opponent team's player's collar in order to stop his momentum. It is a 15 yard penalty.
A true football fan like me won't laugh at your nonsense. I will fight back with my own nonsense instead. Our teams are traditional rivalry in the same division. We are supposed to be enemy. Our fighting result will be determined by who has more nonsense, haha (I am just joking. I am glad to see more Chinese joining the football fan club. nice to meet you).
You are welcome to ask any kind of questions regarding football if you have any confusion. I am far from being an expert but I just have more game watching experience (grin).