The role of syntactic and lexical complexity in the development of verb morphology: subject-verb agreement in French as a second language

Several studies state that subject-verb agreement represents an important area of variation in second language (SL) learners' interlanguage and that its gradual development is very slow, particularly in French as a second language (FSL) (i.a. Nadasi 2001; Bartning & Schlyter 2004; Howard 2006). Even advanced FSL learners use short basic forms, i.e. verb forms devoid of 3rd person plural marking, but used with a plural subject (for example ils *prend). The present study examines the impact of syntactic and lexical complexity on the development of subject-verb agreement in FSL. Inspired by hypotheses put forward by Bartning (1998) and Howard (2013), we will determine in the first part of the study whether syntactic complexity indeed hinders subject-verb agreement and thus if subordinate clauses contain more frequently short basic forms than independent clauses do. The second part of the study will assess the possible impact of lexical complexity on subject-verb agreement in FSL. The lexical richness of the learners' verbal system will be measured to that end and will be linked with their acquisition of subject-verb agreement.