There is no such thing as being bad at native language. You know much more words than I do because english is my second language. Native speakers make way to the language. You know pharasal verbs, you know uses like saying I blow outta here, you know such idoms cuz its your own language. When you watch an american movie, you dont need to see the english subtitle because its your language. You would have no problem with catching their words cuz its your language. Hearing is not enough for me, I also need to see the english subtitle quite often. What you post here dont make sense. You are the language yourself.