A Comprehensive Study of Linguistic, Cognitive, and Pedagogical Challenges in Learning Spanish as a Second Language Among Non-Native Adult Learners

Abstract

This study examines adult learners’ written output of Spanish as a second language (L2), focusing on grammatical density, morphosyntactic complexity, and the correlation between the output and cognitive processing requirement. It employs a multilayered corpus that comprises a more reduced L2 learner corpus, a controlled Spanish baseline corpus and a larger global Spanish reference corpus. This allows descriptive as well as inferential analysis between various levels of proficiency, first-language status, task type, years of education, stay length in a non-native country, and first-exposure age. The findings display that adults’ written production in L2 is fairly high in grammatical density, reflecting a high dependence on explicit morphosyntactic encoding. This grammatical density improves with proficiency, showing structural integration and syntactic embedding at higher proficiency levels. There is consistent variation among L1 groups, which indicates the influence of typological transfer. The type of task constitutes a major factor in linguistic production: more restrictive prompts are more likely to produce a homogeneous pattern of structure, and more open tasks produce more variability. Long-form training, coupled with immersion, is linked to a greater density of grammatical structure and greater target-like organization. Theoretically, the research demonstrates that well-filtered and size-controlled corpora can yield sound and repeatable results regarding morphosyntactic change during adult L2 writing. Its implications include the design of curriculum and the task-sensitive evaluation and planning of instructions, and they add to the corpus-based methods of research in second language acquisition.