回复：老大把我要气死了--帮帮忙

It's your problem.  You have neglected him and always yelling at him.  You have to stop acting like a child, I feel sorry for your son.  You are the one who is losing control and as a result, he is losing control himself because he is unsure of himself, and has no confidence.  For god's sake, he is only a child, not even 7.  I feel like you are crushing his ego.  You need to step back and take a deep breath.  Who cares about piano, sometimes you have to let the small things go, the most important thing is to make him feel happy and good about himself.