CHAPTER 19 INPUT AND SECOND LANGUAGE PROCESSING Kira Gor and Michael H. Long I. FOREIGNER TALK, NEGOTIATION FOR MEANING, AND INPUT AS POSITIVE AND NEGATIVE EVIDENCE From roughly 1970 to 1990, research on the linguistic environment for second language acquisition (SLA) was devoted primarily to descriptive studies of native speaker (NS) speech modifications to nonnative speakers (NNSs) in naturalistic, classroom, and laboratory settings during a process known as negotiation for meaning. The resulting input, together with any written texts that learners encounter, comprises positive evidence, samples of what is grammatical and/or acceptable in the target language and the data from which learners must induce the rules of the new grammar AU :1 . Under certain conditions, the environment also becomes a source of negative evidence, direct or indirect information about what is ungrammatical and/or unacceptable. Negative evidence may be explicit, for example, a grammatical explanation or overt, on- record error correction, or implicit, for example, communication breakdowns perceived as such by the learner, absence of items in the input, or corrective recasts (see below). Findings on speech modifications to NNSs and the resulting input were broadly consistent across settings and, for the most part, echoed those on caretaker speech to young children. Adaptations to L2 acquirers, for example, shorter utterance length, a greater here-and-now orientation, and a preference for yes–no questions over wh-questions, were shown to be predominantly quantitative, resulting in a recognizably different, but grammatically well-formed, ‘‘foreigner register’’ (Arthur, Weiner, Culver, Young, & Thomas, 1980). Qualitative, or categorical, changes resulting in ungrammatical speech of the kind usually referred to, following Ferguson (1975), as ‘‘foreigner talk’’ were rarely observed. (For review, see Gass, 1997, 2003; Long, 1996a). II. INPUT AND COMPREHENSION: SIMPLIFICATION AND ELABORATION During negotiation for meaning, NSs were shown to exploit an extensive repertoire of strategies to avoid communication breakdowns and tactics to repair trouble when breakdowns occurred (Long, 1983a, 1983b). Such modifications in face-to-face 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 445 The New Handbook of Second Language Acquisition Copyright r 2009 by Emerald Group Publishing Limited All rights of reproduction in any form reserved