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Comprehension of English plural-singular marking by Mandarin-L1, early L2-immersion learners

Abstract Previous research has established that early second language (L2) learners in classroom immersion may not ultimately produce all L2 morphosyntactic features as first language (L1) speakers of the language do, whereas L2 comprehension outcomes are reported to be less divergent from those of L1 speakers. However, immersion learners’ L2 comprehension is typically assessed using tasks of holistic understanding, and therefore, little is known about fine-grained comprehension of specific morphosyntactic constructions. To address this, the present study examined online comprehension of English plural–singular marking by Mandarin-speaking, English-immersion learners in Taiwan. This semantically transparent feature differs from the L1 grammar and is a notable area of difficulty for Mandarin-speaking L2-English learners. The present study assesses middle school-aged immersion learners’ comprehension using a visual-world eye-tracking task combined with a picture decision task, comparing results to age-matched English-monolingual controls. After more than 8 years of L2 exposure, the immersion participants showed similarities and differences to monolinguals in plural–singular marking comprehension as measured by eye-tracking, and were less accurate in their interpretations on the picture decision task. This study shows that comprehension differences for a semantically transparent morphosyntactic construction can be apparent even after many years for learners who started immersion at an early age.