The theoretical status of wh-in-situ elements in Mandarin syntactic islands remains a central debate in linguistics. This study provides an empirical evidence from online processing to adjudicate between these theories, employing a self-paced reading (SPR) task with 42 native Mandarin speakers. Results revealed a distinct reading delay pattern extending both within and subsequent to the wh-element inside complex NP islands—a profile that can be systematically explained by Fiengo et al.'s (1988) pied-piping mechanism as well as by Chomsky's (2013, 2015) Label Theory. These findings demonstrate that processing wh-dependencies in islands incurs distributed cognitive costs, supporting the existence of covert syntactic operations. The study establishes a native processing benchmark with dual implications: for syntactic theory, it validates analyses incorporating quantifier raising and labeling-driven movements; for applied linguistics, it provides a psycholinguistic basis for diagnosing L2 acquisition challenges and designing cognitively-grounded pedagogical interventions for complex question structures.
Guanru et al. (2025) studied this question.