WORD CLASS DISTINCTIONS IN SECOND LANGUAGE ACQUISITION
Although the problem of word class has been explored in numerous first language studies, relatively little is known about this process in SLA. The present study measures second language (L2) learners’ knowledge of word class distinctions (e.g., noun vs. adjective) in a variety of syntactic contexts. English-speaking learners of Spanish from third-semester and third-year courses (N= 240) completed a receptive task that presented contrasting forms belonging to the same word family (e.g.,feliz“happy” andfelicidad“happiness”). The results indicate that learners from both groups are often unable to distinguish among word classes. In particular, learners have significant difficulty in discriminating between adjectives and nouns. Although ambiguous surface morphology contributes to word class confusions, the results suggest that L2 learners do not always recognize derivational suffixes that clearly mark word class. These difficulties are interpreted as stemming from weak syntactic morphological knowledge as well as incomplete knowledge of L2 distributional regularities.