Extensive research exists on the effects of task design features on measuring L2 learners’ implicit and explicit knowledge. However, the role of structure difficulty has received limited attention. Additionally, the use of fine-grained measures of implicit knowledge has remained underexplored. To address these gaps, utilizing objective criteria to select easy (plural -s) and difficult (third-person -s) structures, a total of 256 experimental items, equally divided into grammatical and ungrammatical, as well as easy and difficult structures, were developed and administered to 32 advanced L2 learners. A word monitoring task (WMT) assessed their implicit knowledge through reaction time (RT) and grammaticality sensitivity index (GSI), while a timed grammaticality judgment test (TGJT) measured their automatized explicit knowledge through accuracy scores. The WMT results showed longer RTs for ungrammatical items and larger GSI for the plural -s items, revealing participants’ more implicit knowledge of the easy structure. The results of the TGJT revealed that L2 learners judged grammatical items more accurately than ungrammatical ones and the plural -s items more accurately than third-person -s ones, showing participants’ more automatized explicit knowledge of the easy and grammatical structures. The findings highlight the influence of grammaticality and structure difficulty on knowledge retrieval and suggest that advanced L2 learners exhibit stronger implicit and automatized explicit knowledge of the easy structure. These findings underscore the need for tailored instructional approaches to address difficult structures and emphasize the importance of using real-time psycholinguistic measures to examine L2 learners’ implicit knowledge.
Mehraein et al. (Mon,) studied this question.