The human sciences have to assume at least an equal responsibility in establishing the foundations of knowledge. - Michael Halliday

What makes learning possible is that the coding imposed by the mother tongue corresponds to a possible mode of perception and interpretation of the environment. A green car can be analysed experientially as carness qualified by greenness, if that is the way the system works.

A child learning his [her] mother tongue is learning how to name; he [she] is building up a meaning potential in respect of a limited number of social functions. These functions [instrumental, regulatory, interactional, personal, heuristic, and imaginative] constitute the semiotic environment of a very small child, and may be thought of as universals of human culture

Any text in spoken English is organized into what may be called 'information units'. (...) this is not determined (...) by constituent structure. Rather could it be said that the distribution of information specifies a distinct structure on a different plan. (...) Information structure is realized phonologically by 'tonality', the distribution of the text into tone groups.