It is often assumed that metalinguistic performance (e.g., detection of ambiguity, judgments of grammaticality) straightforwardly reflects linguistic knowledge. The inadequacies of such an assumption are explored in this volume, which documents the subtleties of the relationship between metalinguistic performance and knowledge of a second language (interlinguistic competence) from the perspectives of language acquisition theory and cognitive and developmental psychology. This thorough and up-to-date examination of metalinguistic phenomena offers insight to those involved in designing elicitation materials, analyzing and interpreting metalinguistic performance data, and applying such evidence to descriptions of interlanguage grammars and to second-language acquisition theory. The book also contributes constructively to the current debate concerning the role of metalinguistic variables in second-language acquisition, that is, how they ultimately affect success or failure in learning a second language.

The metalinguistic dimension refers to the way in which learners bring to bear knowledge about language into their learning of a second language, the "L2". This book brings together new research on the metalinguistic dimension, given its increasing importance in the study of L2 acquisition. In applied linguistics it is widely accepted that L2 learners develop and use knowledge about language when engaging with the challenging task of acquiring a new language; this applies to both children and adults. It is definitions of the metalinguistic dimension that vary, and findings regarding its role in L2 learning are not necessarily homogenous or compatible. The scope exists for further, empirical, detailed research. This book explores the nature, development and role of the metalinguistic dimension and will be essential reading for all SLA scholars and those working in language and education.

Age effects have played a particularly prominent role in some theoretical perspectives on second language acquisition. This book takes an entirely new perspective on this issue by re-examining these theories in light of the existence of apparently similar non-native outcomes in adult heritage speakers who, unlike adult second language learners, acquired two or more languages in childhood. Despite having been exposed to their family language early in life, many of these speakers never fully acquire, or later lose, aspects of their first language sometime in childhood. The book examines the structural characteristics of "incomplete" grammatical states and highlights how age of acquisition is related to the type of linguistic knowledge and behavior that emerges in L1 and L2 acquisition under different environmental circumstances. By underscoring age of acquisition as a unifying factor in the study of L2 acquisition and L1 attrition, it is claimed that just as there are age effects in L2 acquisition, there are also age effects, or even perhaps a critical period, in L1 attrition. The book covers adult L2 acquisition, attrition in adults and in children, and includes a comparison of adult heritage language speakers and second language learners.

The implicit/ explicit distinction is central to our understanding of the nature of L2 acquisition. This book begins with an account of how this distinction applies to L2 learning, knowledge and instruction. It then reports a series of studies describing the development of a battery of tests providing relatively discrete measurements of L2 explicit/ implicit knowledge. These tests were then utilized to examine a number of key issues in SLA - the learning difficulty of different grammatical structures, the role of L2 implicit/ explicit knowledge in language proficiency, the relationship between learning experiences and learners’ language knowledge profiles, the metalinguistic knowledge of teacher trainees and the effects of different types of form-focused instruction on L2 acquisition. The book concludes with a consideration of how the tests can be further developed and applied in the study of L2 acquisition.

Teachability and Learnability across Languages addresses key issues in second, foreign and heritage language acquisition, as well as in language teaching. Focusing on a Processability Theory perspective, it brings together empirical studies of language acquisition, language teaching, and language assessment. For the first time, a research timeline for the role of instruction in language learning is presented, showing how the field of second language acquisition (SLA) research has developed over the last four decades since Pienemann’s work on learnability and syllabus construction over the 1980s. The book includes studies of child and adult second as well as foreign language acquisition research, covering a wide range of target languages including English, German, Hungarian, Japanese, Norwegian, Polish, Spanish, Swedish, and Turkish. In addition, future extensions of PT are discussed. This volume is designed for advanced students in international programs of SLA and Applied Linguistics as well as for SLA researchers and second and foreign language teachers.

First published in 1994, this crosslinguistic collection looks at changes and developments in language involving gain or loss in structural complexity or utility. The dynamics of these processes of progression and regression are examined at the societal and the individual level, and the two are compared. In the former, the focus is on the social and cultural forces that influence groups of speakers to create new languages or abandon old ones. In the latter, the acquisition and attrition of both first and second languages are considered. Questions raised include: Can parallel structural patterning be observed in whole languages and in the individual's version of a language? Is there parallelism between progression and regression? Can changes occurring in progression and regression be interpreted in a typological framework? These are addressed from sociological, neuropsychological, and linguistic perspectives.

This state-of-the-art volume presents an outstanding collection of 22 studies on current issues facing research in second-language acquisition (SLA). The editors sought contributions for this volume from seasoned veterans of SLA like Lydia White and Susan Gass, from well-known researchers in linguistics and/or first-language acquisition like Haj Ross and Harald Clahsen, and from relative newcomers to the field like India Plough and Jean-Marc Dewaele. The topics covered range from the role of universals at various levels of second-language (L2) knowledge; the way that linguistic knowledge is represented by L2 learners; the changing nature of linguistic theory itself; and the definition of usage phenomena like style shifting and code switching. The introduction to "The Current State of Interlanguage" gives a concise yet detailed overview of research in the field over the past 10 years, and focuses on the present growing concensus on a number of issues that were at one point highly controversial.