This document discusses key concepts in second language acquisition including interlanguage, which refers to a learner's language system with its own rules, and pedagogical effects, which looks at measuring the effectiveness of language teaching practices in promoting second language learning. Interlanguage research rejects the idea that a learner's language is imperfect, but instead its own language developing over time. While studies have evaluated all areas of language learning and teaching methods, it is too much to summarize their findings in general.

1. SECOND LANGUAGE ADQUISITION (ASL) SINDY CRUZ 1103

2. SECOND LANGUAGE ACQUISITION or second language learning is the process by which people learn a second language in addition to their native language. "Second language acquisition" refers to what the learner does; it does not refer to what the teacher does (see "language education" for work on language teaching).

3. INTERLANGUAGE is a term coined by Selinker (1972). Interlanguage scholarship seeks to understand learner language on its own terms, as a natural languagewith its own systematic rules. Interlanguage scholars reject, at least for heuristic purposes, the view of learner language as merely an imperfect version of the target language. Interlanguage work is a vibrant microcosm of linguistics. It is possible to apply an interlanguage perspective to learners' underlying knowledge of the target language sound system (interlanguage phonology),

4. PEDAGOGICAL EFFECTS Efforts have been made to systematically measure or evaluate the effectiveness of language teaching practices in promoting second language acquisition. Such studies have been undertaken for every level of language, from phonetics to pragmatics, and for almost every current teaching methodology. It is therefore impossible to summarize their findings here. However, some more general issues have been addressed.