A Functional Approach to Research on Content-based Language Learning: Recasts in Causal Explanations

There is wide agreement among researchers that content-based language learning (CBLL) instruction is most effective when it provides both meaningful communication about content and intentional language development (e.g., Pica, 2000). However, it is less widely recognized that a systemic functional linguistic (SFL) approach offers a distinctive theoretical perspective and characterization of CBLL and addresses issues of advanced language development which are crucial when the second language is a medium of learning. To demonstrate this, we analyze the grammatical scaffolding by teacher and L2 learner(s) of causal explanations which form part of work by a group of L2 students in a project on the human brain. We show how an SFL analysis reveals quite different aspects of the recast sequences of these data than does a 'focus on form' approach. These aspects include: the lexicogrammar of causal meanings, the place of 'grammatical metaphor' in the processes of language development, the nature of causal explanations as knowledge structures of 'ideational meaning' in discourse, and the role of knowledge structures as bridges between language learning and content learning. The potential of the functional perspective to increase the range and power of research on CBLL considerably is thus seen.