SFL functional perspective
Central to Systemic Functional Linguistics (SFL) is a perspective on discourse as a functional act: discourse is a medium to concrete things in the real world. In order to accomplish something effectively, it is necessary to choose a certain register. Register can be defined as “manner of speaking or writing specific to a certain function, that is, characteristic of a certain domain of communication (or of an institution)” (Bussmann, 1998, p. 994) – e.g. a university instructor speaking to her students. Register unfolds within certain macro (sociocultural) and micro (linguistic) contexts and is made explicit via its three functional constituents: field, tenor, and mode. Field is explained in SFL terms as “nature of social activity” (Martin & Rose, 2007, p. 306-307). Tenor is concerned with relationships between the participants; and mode is understood as a channel of communication. Each of these three register functions correspond to a linguistic metafunction: ideational metafunction, interpersonal, and textual correspondingly. Graphically, this functional perspective can be depicted in the following way:
The SFL functional perspective on discourse (Martin & Rose, 2007, p. 297)
Bussmann, H. (Ed.). (1998). Routledge dictionary of language and linguistics; translated and edited by Gregory Trauth and Kerstin Kazzazi. London: Routledge.
Martin, J.R., & Rose, D. (2007). Working with discourse: Meaning beyond the clause (2nd ed.). London: Continuum.