This article presents the theory of Systemic functional linguistics (SFL), first developed by Michael Halliday, and exemplifies how the theory can be applied in empirical analysisof text and talk. It shows how SFL is centered on the idea that language functions in social meaning making, and how this idea is theoretically elaborated in terms of stratification, metafunctional diversity, systemic choices and registers. The article includes a theoretical description of these four central notions, followed by a presentation of two empirical studies. Both studies explore lexicogrammatical and semantic choices within the ideational metafunction, though in different registers.The first study is an analysis of the use of grammatical metaphor in text written by monolingual and multilingual upper secondary school students. Grammatical metaphor is the realization of meaning in atypical, or incongruent, ways. In the study, grammatical metaphor is a developmental trait, allowing students to express specialized meanings through new combinations between semantics and lexicogrammar.In the second analysis SFL is applied on talk in interaction and combined with activity analysis. The study explores the successive instantiation of the meaning potentialof language in a certain context, namely when participants talk about thinkingin radio phone-in counseling conversations. An analysis within the ideational metafunctioncombined with the notion of communicative projects describes how, in this specific case, the participants’ lexicogrammatical choices between a verb and a nominalform contributes in a critical way to a successful outcome of the ongoing counseling activity.
2014. Vol. 52, 9-30 p.