"Language is as it is because of what it has to do" (Halliday, 1978, p. 19).

"It is important for students to develop academic register options in different disciplines because particular grammatical choices are functional for construing the kinds of knowledge typical of a discipline. Academic registers are not just pretentious ways of using language that only serve to exclude the uninitiated. The kinds of meanings that are created in academic contexts often cannot be expressed in the language of ordinary interaction. Instead, school-based tasks require particular ways of presenting information; the ways construed through academic registers."

"Scientific concepts (relevant to science, history, and other disciplines) have to he consciously learned, typically through schooling; different from the' everyday' concepts that are learned through daily life. This distinction is important for understanding the contribution of schooling to the development of language and thought. Scientific explanations sometimes contradict the interpretations common sense would suggest. The language through which scientific concepts are construed is different from the language through which everyday concepts are construed, and learning the language has to he part of learning the concepts, as the concepts are constructed through language."

"Academic registers are functional for their purposes, to enable the presentation of information in the structured, authoritative ways expected in school contexts. Scientific English evolved the way it did as scientists developed the grammatical and lexical means of presenting scientific findings to share information about the experiments they had conducted. In order to talk about processes in the world as scientists do, they needed to name those processes and talk about relationships among them. Technical vocabulary, expanded nominal groups and nominalisation, and construal of logical relationships in relational processes, the syndrome of features created through grammatical metaphor, makes this possible". (Schleppegrell, 2004, p. 137).