The main language in Erbil is Kurdish language, for managing daily life in Erbil is much better to know speak Kurdish language. A few numbers of Kurdish people are able to speak Arabic beside of their Kurdish but those are the old generation. New generation, I mean the youngs, very rarely you could find one who speaks Arabic.
I just saw your mesage requesting arabic teacher i wounder if you still looking for that cause i am kirdish and i do speake arabic level 5;in additional i have i collage degree and i was interpreter for along time .