回复：回复：另外他有点坐不住，20分钟后就不能集中了，这正常吗？我是不是该带他看医生？谢谢。

Don't worry. When I taught my counting, it also took long time for him to catch it all. Overall, I gave up and let teacher to teach him at school. amazingly, he learned fast at school, maybe teachers have their to teach small kids.