effect of metalinguistic feedback on chilean preservice teachers’ written use of the third person singular suffix -s^1

This study addresses the impact of 2 types of written corrective feedback (wcf) on the acquisition of the third person singular -s in english. the study followed a quasi-experimental design: 2 experimental groups and 1 control group that included 57 preservice teachers from a chilean university. the experimental groups underwent a treatment based on the provision of direct metalinguistic feedback (group 1) and indirect metalinguistic feedback (group 2). the control group did not receive any type of wcf. at the end of the treatment, a posttest was run and, 1 month later, a delayed posttest was given. finally, a semistructured interview was conducted in order to identify the l2 learners’ perceptions about the provision of wcf through a wiki environment. there was no significant difference between the experimental groups on the posttest. however, on the delayed test, group 2 outperformed group 1.