We present, in this paper, a comparative study between the theoretical approaches developed in Sociodiscursive Interactionism (ISD) and in Systemic Functional Linguistics (LSF). We aim to identify the similarities and/or differences between these two theoretical currents, since both have contributed significantly to the linguistic studies developed in Brazil, whether in the theoretical or applied field. We are mainly based in Bronckart (2003BRONCKART, Jean-Paul. 2003. Atividade de linguagem, textos e discursos: por um Interacionismo sócio-discursivo. Trad. Anna Raquel Machado, Péricles Cunha. São Paulo: EDUC.; 2013_____. 2013. The language system at the heart of the systems make up the human being. In: Gouveia, Carlos; Alexandre, Marta Filipe. Languages, metalanguages, modalities, cultures: functional and socio-discursive perspectives. Lisboa: BonD & ILTEC. p. 65-84.) e Halliday and Matthiessen (2014)_____; MATTHIESSEN, Christian. 2014. An Introduction to Functional Grammar. Hodder Education. . The results of the research demonstrate that there are similarities between the two theoretical currents in the way they both conceive language, in how they see the language in use, and also in their conceptions of text. Differences have been identified in the way that linguistic theories address the question of type of discourse and textual genre.
Applied Linguistics; language; grammar; text