ABSTRACT
Systemic Functional Linguistics (SFL) (Halliday 1978, 1994; Halliday and Matthiessen, 2004; Martin and Rose, 2003; among others) is a social theory of language that provides researchers with unique constructs, tools, and insights for the study of advanced L2 capacities. In addition, SFL is particularly well suited to provide theoretical guidance in longitudinal investigations of L2 development. In this chapter, we discuss SFL principles, highlighting their relevance for the longitudinal study of advanced L2 capacities. We also illustrate these principles with data and findings from our longitudinal research program involving Spanish heritage language learners in US higher education contexts. SFL theory situates language development in its sociohistorical context linking patterns of language use to particular culturally relevant situations. In academic contexts language is used to display information using technical lexicon, with high degrees of structure and with an authoritative stance (Martin, 1993; Schleppegrell, 2004). Therefore, in this framework language development demands longitudinal measures that gauge the control users develop over time of particular lexico-grammatical patterns (e.g., grammatical metaphor, lexical density, grammatical complexity, clause combining and engagement) that index an academic context. The discussion will be fleshed out with examples from two studies in which we tracked oral and written development of Spanish in heritage speakers who are using Spanish in academic and professional contexts in the US. From this perspective, advanced language development was defined as changes that develop gradually over time in relation to academic contexts where there are institutionalized ways of using language that characterize disciplinary discourse communities.
