This quasi-experimental study investigated the potential benefits of two corrective feedback techniques (recasts and prompts) for learners of different proficiency levels. Sixty-four students in three intact grade 6 intensive English as a second language classes in the Montreal area were assigned to the two experimental conditions-one received corrective feedback in the form of recasts and the other in the form of prompts-and a control group. The instructional intervention, which was spread over a period of 4 weeks, targeted third-person possessive determiners his and her, a difficult aspect of English grammar for these Francophone learners of English. Participants' knowledge of the target structure was tested immediately before the experimental intervention, once immediately after it ended, and again 4 weeks later through written and oral tasks. All three groups benefited from the instructional intervention, with both experimental groups benefiting the most. Results also indicated that, overall, prompts were more effective than recasts and that the effectiveness of recasts depended on the learners' proficiency. In particular, high-proficiency learners benefited equally from both prompts and recasts, whereas low-proficiency learners benefited significantly more from prompts than recasts. The last 10 years have witnessed a steady increase in the number of studies that have examined the effects of corrective feedback~CF! on second lan-guage~L2! learning+ This includes both descriptive and experimental research This study is based on the first author's Ph+D+ research~Ammar, 2003!+ We gratefully acknowledge the cooperation of the participating teachers and students+ We thank Patsy Lightbown, Roy Lyster, Pavel Trofimovich, and the anonymous SSLA reviewers for their valuable input and feedback on earlier versions of this paper+

A meta-analysis was conducted to investigate the effects of explicit and implicit instruction on the acquisition of simple and complex grammatical features in English. The target features in the 41 studies contributing to the meta-analysis were categorized as simple or complex based on the number of criteria applied to arrive at the correct target form (Hulstijn & de Graaff, 1994). The instructional treatments were classified as explicit or implicit following Norris and Ortega (2000). The results indicate larger effect sizes for explicit over implicit instruction for simple and complex features. The findings also suggest that explicit instruction positively contributes to learners' controlled knowledge and spontaneous use of complex and simple forms.Keywords instructed SLA; explicit/implicit instruction; explicit/implicit knowledge; meta-analysis In the instructed second language acquisition (SLA) literature there is a general consensus that instruction is beneficial for second language (L2) development (Ellis, 2001;Norris & Ortega, 2000;Spada, 1997). Several issues remain, however, including what types of knowledge and language abilities benefit We are grateful to the anonymous reviewers who provided constructive input and valuable feedback on an earlier version of the manuscript. We are particularly grateful for the information and guidance from one of the reviewers with particular expertise in conducting meta-analyses. Although the article has improved considerably from the input from all reviewers, we alone are responsible for any errors or omissions.

The paper is organised around the seven research questions listed below. The majority of the studies Lang. Teach. 30, 73-87.

Some researchers suggest that recasts are effective in showing learners how their current interlanguage differs from the target (Long & Robinson, 1998). Others have argued that recasts are ambiguous and may be perceived by the learner as confirmation of meaning rather than feedback on form (Lyster, 1998a). We review research on the effectiveness of recasts in first and second language acquisition, paying particular attention to how recasts have been defined and how their impact has been assessed

The developing oral English of approximately 100 second language learners (four intact classes) was examined in this study. The learners were native speakers of French (aged 10-12 years) who had received a 5-month intensive ESL course in either grade 5 or grade 6 in elementary schools in Quebec. A large corpus of classroom observation data was also analyzed.Substantial between-class differences were found in the accuracy with which students used such English structures as progressive -ing and adjective-noun order in noun phrases. There was some evidence that these differences (which were not correlated with performance on This research was funded by grants from the Quebec Ministry of Education's research granting agency (Fonds pour la formation de chercheurs et I'aide a la recherche) and the Social Science and Humanities Research Council of Canada, and by supplementary grants from several of the school boards in which the intensive programs have been developed. We wish to acknowledge the exceptional cooperation we have always enjoyed in dealing with students and teachers in the programs. We are grateful to our fine research assistants who have helped us at every stage of the research. We particularly acknowledge the help of Randall Halter,