Research on spontaneous language acquisition both in children learning their mother tongue and in adults learning a second language has shown that language development proceeds in a stagewise manner. Learner utterances are accounted for in terms of so-called 'learner languages'. Learner languages of both children and adults are language systems that are initially rather simple. The present monograph shows how these learner languages develop both in child L1 and in adult L2 Dutch. At the initial stage of both L1 and L2 Dutch, learner systems are lexical systems. This means that utterance structure is determined by the lexical projection of a predicate-argument structure, while the functional properties of the target language are absent. At some point in acquisition, this lexical-semantic system develops into a target-like system. With this target-like system, learners have reached a stage at which their language system has the morpho-syntactic features to express the functional properties of finiteness and topicality. Evidence of this is word order variation and the use of linguistic elements such as auxiliaries, tense, and agreement markers and determiners. Looking at this process of language acquisition from a functional point of view, the author focuses on questions such as the following. What is the driving force behind the process that causes learners to give up a simple lexical-semantic system in favour of a functional-pragmatic one? What is the added value of linguistic features such as the morpho-syntactic properties of inflection, word order variation, and definiteness?

other aspects of developing grammars. And this is, indeed, what the contributions to this volume do. Parameterization of functional categories may, however, be understood in different ways, even if one shares the dual assumptions that substantive elements (verbs, nouns, etc. ) are present in all grammars and that X-bar principles are part of the grammatical knowledge available to the child prior to language-specific learning processes. From these assumptions it follows that the child should, from early on, be able to construct projections on the basis of these elements. The role of functional categories, however, may still be interpreted differently. One possibility, first suggested by Radford (1986, 1990) and by Guilfoyle and Noonan (1988), is that children must discover which functional categories (FC) need to be implemented in the grammar of the language they are acquiring. Another possibility, first explored by Hyams (1986), is that a specific category is present in developing grammars but that parameter values are set in a way deviating from the target adult grammar, corresponding, however, to options realized in other adult systems. A third option would be that these categories might be specified differently in developing as opposed to mature grammars. All three are explored in the papers collected in this volume. Before outlining the various hypotheses in more detail, however, I would like briefly to sketch the grammatical context in which the following debate is situated. 2.

This study investigates the acquisition of Functional Categories (e.g., INFL (AGR, TNS), DET, COMP) from the perspective of self-organization in generative grammar. Language is conceived of as a dynamical system which evolves in time and bifurcates when critical thresholds are reached. The emergence of syntax as evidenced by the acquisition of Functional Categories is the major bifurcation in child language acquisition. Target values of syntactic parameters are attractors which children approach on individual trajectories. A proposed tripartite scenario of change - from a simple stable state A, via symmetry-breaking in a liminal phase B characterized by variation, to a new complex stable state C - accounts for the dynamics in early grammatical development. Traditional generative issues, such as the acquisition of case-marking, finiteness, V2, and wh-questions, are discussed as well as new issues, such as functional neologisms, and sentential blends. Dynamical notions like precursor, oscillation, symmetry-breaking, and trigger are important explanatory tools. The growing child phrase marker is a fractal mental object which represents syntactic information by way of self-similar extended projections. The book addresses researchers in language acquisition from various theoretical camps: generative, functional, connectionist, by giving new answers to old questions in the light of a novel challenging theory: self-organization.

This book develops ideas of Minimalist syntax to derive functional categories from the partially-ordered features expressed by functional elements, thereby dispensing with functional categories as primitives of the theory. It generalizes attempts to do this in the literature, while drawing significant empirical consequences from general constraints formulated to block overgeneration. The resulting theory of the construction of functional categories is applied to various problems in syntactic analysis and comparative and historical syntax, including variation across Germanic languages in patterns of verb-second and in the occurrence of expletive subjects in existential constructions, verb positions in Old and Middle English, problems regarding the placement of clitic pronouns in Romance languages and Modern Greek, and some previously unexamined structures of reduced clause coordination in colloquial English. Facts from early stages of the acquisition of syntax are shown to follow from the mechanisms for the projection of functional features as functional categories, exercised before all of the features for a language, along with their ordering and feature co-occurrence restrictions, have been acquired. It is observed that child acquisition of functional elements exhibits successive developmental stages, each characterized by the number of clausal functional elements which can be represented together within a clause. This, and facts regarding the lag in development of functional categories by children with specific language impairment, are shown to be not entirely reducible to limitations in working memory or processing capacity, but to depend in part on the growth of representational resources for the projection of functional categories.

Research on spontaneous processes of language acquisition has shown that early learner systems are based on lexical structures. At some point in acquisition this lexical-semantic system is given up in favour of a target-like functional category system. This work deals with the driving forces behind the acquisition of the functional properties of inflection, word-order variation, definiteness and agreement.

Dummy auxiliaries are seemingly superfluous words that appear in learner varieties across languages. This volume is an up-to-date overview of research on dummy auxiliaries with contributions covering English, Dutch, German, French, Cypriot-Greek, first and second language acquisition, and specific language impairment as well as dialectal variation.

Acquisition of the native language proceeds in a stage-wise manner for both typically developing (TD) children and children with developmental language disorder (DLD). As shown in TD children learning Dutch and German, the ability to establish contextual cohesion serves as the driving force to proceed from a simple, lexical system to a more complex, functional system. It is argued that precisely this ability is challenged in children with DLD. The present book offers an account of the functional linguistic features fit to achieve contextual cohesion in language production. It provides a rationale for practitioners to develop linguistically founded tools to be used in speech therapy.