2Ammar, Ahlem & Nina Spada 2006 One size fits all? Recast, prompts, and L2 learning. Studies in Second Language Acquisition 28: 543--574.
3Cohen, Jacob 1988 Statistic Power Analysis for the Behavioral Sciences (2nd ed.). Hillsdale, NJ. Erlbaum.
4DeKeyser, Robert M. 1993 The effect of error correction on L2 grammar knowledge and oral proficiency. Modern Language Journal 77: 501--514.
5Doughty, Catherine & Elizabeth Varela 1998 Communicative on focus on form. In Catherine Doughty & Jes- sica Williams (eds.), Focus on Form in Classroom Second Language Acquisition. New York: Cambridge University Press.
6Ellis, Rod 2007 The differential effects of corrective feedback on two grammatical structures. In A. Mackey (Ed.), Conversational Interaction in Second Language Acquisition. New York: Oxford University Press.
8Ellis, Rod, Shawn Loewen & Rosemary Erlam 2006 Implicit and explicit corrective feedback and the acquisi- tion of L2 grammar. Studies in Second Language Acquisition 28 : 339-- 368.
9Ellis, Rod * Younghee Sheen 2006 Reexamining the role of recast in second language acquisition. Studies in Second Language Acquisition 28 : 575--600.
10Han, Zhaohong 2002 A study of the impact of recasts on tense consistency in L2 output. TESOL Quarterly 36:543--572.
