The development of morphological complexity: A cross

Studies in second language acquisition (SLA) increasingly rely on measures of linguistic complexity to assess second language (L2) proficiency and development. While an important number of studies have risen to the call of studying a broader range of complexity related constructs (Bulté and Housen, 2012; Norris and Ortega, 2009), few have examined morphological complexity, instead focusing on syntax and lexis. The use of morphology measures is especially warranted in light of complexity trade-offs believed to occur both in language development – when growth in one linguistic domain (e.g. syntax) is temporarily prioritized over growth in another (e.g. morphology) – as well as crosslinguistically, in the form of balancing effects between different domains of the linguistic system. From both a cross-linguistic and developmental perspective, then, the current emphasis in SLA research on measures of syntactic complexity does not comprehensively gauge overall (grammatical) complexity in learner data. This study focuses on the development of morphological complexity using three previously proposed measures based on the notion of morphological diversity, with special attention to the verbal inflectional system (Horst and Collins, 2006; Malvern et al., 2004; Pallotti, 2015). Not only does the verbal system pose significant challenges to language learners, it is also the locus of important differences between inflectionally richer languages, like French, and inflectionally poorer languages, like English. The study investigates cross-linguistic differences in the development of morphological complexity and the effectiveness of the three morphological complexity measures as indicators of proficiency. The analyses were carried out on a multilingual corpus of 100 L2 French and 100 L2 English oral narratives, representing four different proficiency levels in both languages. Results indicate a more continuous increase of morphological complexity in L2 French than in L2 English and underline the importance of morphology as an essential component of a multidimensional view of linguistic complexity in SLA