Number Agreement Attraction in L2 Sentence Processing—Evidence From Highly Proficient Chinese–English Bilinguals

Aims and Objectives: It remains debated whether second language learners whose native language lacks agreement morphology are sensitive to number agreement attraction. This study investigates whether highly proficient Chinese–English bilinguals are susceptible to number agreement attraction in L2 sentence processing and how subject modifier structures and verb types modulate this effect. Methodology: Participants completed an acceptability judgment task and a self-paced reading task to assess reading times and accuracy rates for sentences containing potential number agreement attractors. Data and Analysis: Data from 38 proficient Chinese–English bilinguals were analyzed using linear mixed-effects models (LMMs) to examine sensitivity to number agreement attraction across the different syntactic and verb conditions. Findings: Results revealed that proficient Chinese–English bilinguals were sensitive to number agreement attraction and displayed grammatical asymmetry, indicating reliance on cue-based memory retrieval mechanisms. Unlike native speakers, they exhibited inhibitory rather than facilitatory interference for number-matching attractors, reflecting L1–L2 processing constraints. Originality: This study distinguishes itself by isolating the specific effects of subject modifier structures and verb types on agreement attraction in L2 learners whose L1 lacks morphological agreement markers. Implications: Findings enhance understanding of L2 subject–verb agreement processing and demonstrate how cross-linguistic differences shape attraction interference patterns.