The relative effects of enhanced and non-enhanced structured input on L2 acquisition of Spanish past tense

Research on how textual enhancement (TE) affects classroom-based L2 acquisition of grammatical morphemes has shown mixed results. When enhanced conditions were compared with un-enhanced conditions; some studies demonstrated significant effects for textual enhancement; some reported no effect or negative effects and others reported only partial effects for textual enhancement. In contrast; research on how structured input (SI) impacts L2 acquisition of grammatical morphemes has shown consistently beneficial effects. Combining TE and SI; the present study introduces textually enhanced structured input (TESI) as a treatment. The main purpose of this study is to present and examine the differential effects of two types of input-based language instruction on how learners interpret and produce the third-person singular form of the Spanish preterit. Although TESI did not prove to be more beneficial than the un-enhanced treatment in the present study; both types of instruction resulted in improvement over time without explicit grammatical information.