"Language abilities" refers to the skills and knowledge a person has in using and understanding a specific or multiple languages. It includes being able to speak, read, write, and comprehend the language(s) effectively. Full definition
Except where there are issues of literacy or English language ability, we ask that the questionnaire be filled out by the prisoner, not by a friend or family member. (exonerate.org)
They usually have advanced language abilities in comparison with children of the same age. (hoagiesgifted.org)