His confusion about English usage is ___, because he is a native speaker and he is an English expert.
I find the word 'incomprehensible', whose defination in Collins dictionary is:
- incapable of being understood; unintelligible.
That seems doesn't fit the meaning of a word I am looking for to fill that blank, I want a word that mean 'it almost doesn't make sense to understand', not because 'it's too difficult (like a math puzzle) to understand.' is there a more precise word for that?