Taking into consideration some gaps observed in SLA research--noticing, recasts, input enhancement (IE),…-- and in CALL/CMC research, a study was conducted among 12 advanced FL Spanish learners to assess whether and how, by communicating with a Spanish native speaker in 5 chat-room sessions, their language competence would develop in the following areas: 1) communication strategies; 2) communicative acts; and 3) grammatical knowledge of verb tense-aspect-mood (TAM) assignation. Subjects were assigned to a specific feedback condition/group (A: +recast, -enhancement; B: +recast, +enhancement; and C: no feedback) under which their TAM errors were treated in the sessions. Few research studies have concentrated on the effectiveness of recasts for grammatical acquisition; rather, they tend to focus on conversational aspects (e.g. Lyster&Ranta, 1997; Ohta, 2000) while the scarce grammar-based recast research has yielded positive results (e.g. Doughty&Varela, 1998; Ishida, 2004; Mackey&Philp, 1998). On the other hand, IE, typically an enhancement of the perceptual salience of input in applying the "input flooding" technique (Francis, 2003), has yielded mixed results, but some studies have found a facilitative effect for IE (Doughty, 1991; Francis, 2003; Jourdenais et al., 1995; Shook, 1994). Because of their relatively ineffective, rather implicit nature when used in isolation, in this study recasts were combined with IE assuming that IE--a tool not traditionally used in SLA as an additional measure of feedback--might strengthen the recast and render it more effective for uptake of the linguistic forms. Based on the properties of the resulting combined feedback (group B: enhanced recast), it was anticipated that enhanced recasts would be a more powerful tool, and, as a result, the following sequence of gain in grammatical knowledge would be found: group B (enhanced) > group A (non-enhanced) > group C (no feedback). The findings reveal that groups B and C had the highest overall gains in verb TMA assignation, and group B was superior in most grammatical contexts. As for communication strategy and communicative act use, the sequence of gain was: A > B > group C. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]