Is non-redundant inflectional morphology easier to learn? An investigation of Processing instruction role in processing redundant English verbal inflections.

The present study investigated the effects of processing instruction (PI) on the processing and production of verbal inflectional morphology in English with varying redundancy: third person singular -s, regular past form -ed, and present progressive -ing. Ninety-three adult L2 English classroom learners in Saudi Arabia were divided into three groups receiving different teaching interventions over eight weeks: one based on standard PI, another with a novel modified PI approach including communicative activities (MPI), and a control group. Participants completed an offline interpretation task, an online self-paced reading (SPR) task and online elicited imitation (EI) task before and after intervention, then 12 weeks later in a delayed post-test. Results showed that both groups had similar performance in the offline interpretation task, but the MPI group outperformed the PI group on both online SPR and EI tasks The SPR task results also showed that the MPI intervention equally affected all the target inflections despite their differing redundancy levels. We therefore claim that MPI can be an effective classroom method for acquisition of L2 English verbal morphology.