This document discusses the metafunctions of systemic functional linguistics (SFL) as developed by M.A.K. Halliday. It outlines that SFL identifies three metafunctions: the ideational, which deals with experiences and processes in the world; the interpersonal, which involves the interaction between participants; and the textual, concerning how text is structured through cohesion. Cohesion involves reference, substitution, ellipsis, conjunctions, and lexical ties. Lexical cohesion occurs through reiteration like synonymy and collocation of regularly co-occurring words within a context.