Thomas Amanda L.R. Divergence and mismatches in Portuguese morphology and syntax

Trinity College, University of Oxford, 2021. — 446 p.This thesis proposes an integration of Paradigm Function Morphology (PFM) as the morphological component within the Lexical-Functional Grammar (LFG) architecture, applying the combined theoretical framework LFG-PFM to account for diachronic data. The theory is developed by application to two case studies from Portuguese involving mismatches between different levels of grammatical structure and resulting in divergence between varieties of the language. In each case, I give a new presentation of the Portuguese phenomena, which have not previously been treated in LFG or PFM.
The first case study is the double past participle phenomenon, in which an arbitrary set of verbs unexpectedly have two past participle forms split between active and passive contexts, where most verbs only have one form. There is significant variability in the application of the phenomenon to lexemes over time and across varieties of Portuguese. I show that this can be successfully analysed in LFG-PFM using lexical specification and inflection classes. In addition, I clarify the role of irregular stem roots in the double past participles and identify possible trajectories of change. The second case study is Portuguese grammaticalised pronouns, which have developed from noun phrases and show interesting mismatch behaviour in their agreement patterns. My analysis uses distinctions in the PERSON feature at the levels of semantic structure and functional structure to capture various mismatch patterns seen across varieties of European and Brazilian Portuguese, including differences in the choice of coreferent pronouns and verb agreement.
The two case studies together demonstrate the success of the LFG-PFM approach of treating separate modules of the grammar independently. This allows a fine-grained account of the incremental changes that contribute to the development of distinct varieties of a language, and offers new insights into the morphological and syntactic phenomena at issue.