ABSTRACT
This chapter examines alternation between the complementisers that and zero, a ubiquitous variable in English. While explanations for this alternation abound (grammaticalization, complexity, frequency, processing, lexical effects), Cheshire offered a nuanced perspective in which complementiser that engages both cognitive and social constraints in the joint creation of discourse. We take up this observation, analysing over 4,000 tokens of complementiser variation in a corpus of spoken vernacular Canadian English. Linguistic predictors constrain variation overall, yet there are over-riding social and discursive pressures. Complementiser that surfaces when it serves a cooperative function, signalling clausal boundaries in complex structures to help interlocutors navigate interaction as it unfolds. We support Cheshire’s call for more attention to interactional pressures on linguistic variation. The multiple perspectives offered by socially embedded data are essential for understanding not only linguistic systems but also how interactional dynamics contribute to conversational and social settings.
