Not all learners benefit equally

Abstract This longitudinal study examines how initial comprehensibility and the amount of L2 use interact to predict Mandarin learners’ Spanish comprehensibility after study abroad (SA). Twenty-seven L1 Mandarin learners of Spanish completed story-retelling tasks before (T1) and after (T2) one academic year of study in Spain. Their speech was rated for comprehensibility. We modeled the T2 comprehensibility score based on the T1 comprehensibility score and the L2 use score. The L2 use score was composed of listening and speaking frequencies in Spanish relative to Mandarin during SA. While the L2 use score positively predicted T2 outcomes, the benefit of L2 use was significantly greater for learners with lower initial comprehensibility than for learners with higher initial comprehensibility. These findings suggest that immersion benefits less proficient learners more than advanced learners. For more advanced learners, naturalistic immersion may not be sufficient to further improve oral skills; targeted pronunciation training may be necessary.