Even Muggles like yourself should be celebrating,this happy,happy day.

问题描述:

Even Muggles like yourself should be celebrating,this happy,happy day.
句中为什么是like yourself,不是like you
句中为什么should be celebrating,不是should celebrate

语法上you也是对的,这里用yourself是加强语气,强调对方就是一个muggles.在这里就是可以贬低和侮辱对方.
be celebrating表示正在进行的状态
即使像你这样的麻瓜都应该在庆祝这开心的一天才对.