| Previous research investigating the L2 acquisition of Spanish 3 rd-person object pronouns has identified their respective form-function relationships as being an acquisitional challenge (Andersen, 1983; 1984; Liceras et al. 1997; VanPatten, 1990; Zyzik, 2004). That is, the direct-object pronominal forms are grammatically multifunctional; la (her), lo (him), and las/los (them) also represent definite articles in specific contexts. L2 learners' ability to produce third-person forms in direct-object contexts, thus, is dependent on whether or not they have reached a multifunctional stage of form-function mapping (Andersen, 1990).;Empirical studies confirm the acquisitional challenge resulting from multiple form-function relationships but have not investigated the development of individual direct-object third-person forms subsequent to their emergence among advanced L2 learners. Consequently, we do not know the sequence in which third-person forms are acquired, nor do we know the extent to which psycholinguistic operating principles guide the interlanguage development of the target structure.;The present study provides a novel approach to investigating the L2 acquisition of Spanish object pronouns by utilizing a multifaceted analysis of L2 production. First, a function-form analysis was used to trace the emergence of new forms to realize the role of direct object. Second, a form-function analysis was conducted to reveal the distribution of individual forms to a variety of different grammatical functions. Third, an analysis of the appropriate use of forms produced revealed L2 development toward a nativelike trajectory. Finally, statistical analyses were conducted to reveal main effects of external and linguistic factors on production.;A cross-section of L2 learners (n=103) and one group of native speakers (n=17) conducted a film-retell task, requiring oral and written production. Results reveal a main effect for mode such that, (1) early-level learners produced more clitic pronouns in written discourse than in oral ( p<.01), and (2) all proficiency levels produced nativelike morphology for gender more often in written discourse (p<.01). In addition, results indicated the sequence of acquisition following the route of person, number, and gender as proficiency levels rose, regardless of mode (p<.05). Finally, four stages of interlanguage development were identified in the L2 learners' transition from one-to-one form-function mapping to multifunctionality. |