Yes. All language proficiency consists of several different components. So when I think of language proficiency, I always start thinking of phonology, of phonological component. So in academic English, a young child, anybody, needs to know the phonological component consisting of the sounds of the English language.
And they would have to know how to spell in English and that's particularly important in academic language, but not so important in informal language. And they would have to know the phonological features of the English language.
For example to pronounce academic words. Knowing the difference, for example, between anthropology and a shift in stress, anthropological; morphology, morphological…