Applying local grammars to the diachronic investigation of discourse acts in academic writing: The case of exemplification in Linguistics research articles

This paper proposes a local grammar approach to investigating diachronically discourse acts in academic texts, aiming to offer an additional method for diachronic studies of academic discourse. Local grammars capture the patternings of the realizations of discourse acts at both the lexicogrammatical and discourse-semantic levels; as such they offer a way to explore how the realizations of a given discourse act may vary across time periods or contexts. The proposed local grammar approach is subsequently demonstrated with a study investigating the changing patterns of exemplification in Linguistics research articles, which shows that academic writers of Linguistics nowadays tend to exemplify in simpler and more explicit ways and by presenting subcategories. It is further argued that such investigations complement diachronic investigations of other linguistic features in academic texts, thereby enriching the toolbox of EAP and ESP studies. • A local grammar approach to diachronic studies of discourse acts was proposed. • A diachronic investigation of exemplification in Linguistics RAs was performed. • Exemplification is primarily used to specify general categories in Linguistics RAs. • Writers of Linguistics RAs nowadays exemplify in simpler and more explicit ways.