This study investigates whether child second language (L2) learners can use syntactic information during the processing of sentences involving unbounded dependencies and how their processing patterns compare to those of child monolinguals and adult L2 learners. Through a self-paced reading experiment involving the numeral quantifier (NQ) construction in Korean, we tested participants’ sensitivity to agreement violations between a noun phrase (NP) and an NQ in local and nonlocal conditions. The results showed that a subset of child L2 learners who demonstrated target-like knowledge of NP-NQ agreement in an offline task spent a longer processing time in the NP-NQ mismatch than in the NP-NQ match condition, in both local and nonlocal contexts. These child L2 learners’ processing patterns were comparable to those observed in child monolinguals and adult L2 learners. These findings suggest that child and adult L2 learners rely on the same system of syntactic representations and processing mechanisms that guide first language processing.
