Integrating syntactic and prosodic boundary cues in second language processing: Evidence from L1-Chinese L2-English learners and L1 English speakers

It remains unclear whether second language prosody–syntax integration resembles native language mechanisms. This study examines how first language (L1) Chinese second language (L2) English learners integrate prosody and syntax compared with native English speakers, and explores L1 Chinese and L2 English processing within L2 learners. Using the Rapid Prosody Transcription method, 89 participants, including native English speakers and Chinese L2 learners, judged prosodic boundaries under manipulated acoustic and syntactic conditions. Results showed that Chinese L2 learners exhibited stronger syntactic constraints in English sentence judgments compared with native speakers. Furthermore, they relied more on syntactic information when processing L2 English than L1 Chinese. These results were examined in relation to the Shallow Structure Hypothesis (SSH), as heuristic processing appears to dominate in L2, leading learners to prioritize syntactic over acoustic cues for rapid and global interpretation. This study proposes that ‘shallow’ in the SSH indicates that L2 processing prioritizes higher-level information.