More languages, fewer strategies? linguistic repertoires and the diminishing returns of grammar learning strategies

This study examined predictors of grammar achievement among 196 multilingual university students learning English as a foreign language in France. Using multiple regression with moderation analysis, we investigated how grammar learning strategies, beliefs about grammar instruction, self-efficacy, linguistic repertoires, and language aptitude predicted three components of grammar knowledge: implicit knowledge, explicit knowledge, and applied knowledge. Linguistic repertoire size emerged as the strongest predictor of implicit and applied knowledge, while the model for explicit knowledge was non-significant, suggesting this component develops through mechanisms not captured by our predictor set. Learning strategies showed no main effects on any outcome; however, a significant moderation effect was found for affective strategies, with similar but weaker trends for cognitive and multilingual strategies, suggesting automatisation of learning processes with increasing multilingual experience (i.e. larger linguistic repertoires). Self-efficacy showed a similar pattern, predicting implicit knowledge only among less multilingual learners. Focus on form beliefs uniquely predicted applied knowledge regardless of repertoire size. The findings challenge assumptions about the universality of learning strategy instruction and highlight the need for differentiated pedagogy based on learners’ multilingual profiles.