“Black and White” or “White and Black”: The Processing of L1–L2 Structurally/Semantically Congruent Binomials by Japanese Learners of English

This study investigated whether L1–L2 structural/semantic congruency affects the processing of binomials in L2 English. Specifically, it aimed to examine how L2 learners process form‐meaning congruent binomials (completely‐congruent), semantically congruent but incongruent in form (reverse‐congruent), and incongruent (L1‐ and L2‐only) binomials compared to a baseline. Using reaction time data from a phrase decision task with 124 Japanese learners of English and 80 L1 English speakers as a control, the results revealed that L2 learners exhibited a significant processing advantage for both completely‐congruent and reverse‐congruent binomials over the baseline. Notably, this advantage persisted in both conventional and reversed word orders for these two categories, suggesting that semantic information may play a more crucial role in L2 processing than structural alignment. In contrast, incongruent binomials showed no significant processing advantage. Furthermore, while L1 English speakers were sensitive to L2 (English) phrase frequency, L2 learners' processing was more robustly influenced by L1 (Japanese) phrase frequency, with L2 frequency showing no significant effect. These findings are interpreted in relation to a common semantic representation account, where L1 and L2 multiword expressions and constituents are linked via shared conceptual representations, and suggest that L2 processing of congruent binomials may be meaning‐driven with the potential additive influence of L1 phrase frequency.