The current reliance on linguistic data for inferences about the concept–word relationship has led to serious questions being raised regarding the existence and facilitative role of prelinguistic categories in early word learning. In three experiments a multiple habituation paradigm was used to examine the ability of 7- and 9-month-old prelinguistic infants to form a natural, basic-level object category. In Experiment 1, 9-month-old infants appeared to form a category of bird, but only when habituated to prototypical exemplars as opposed to poor exemplars. Discriminability between prototypical habituation exemplars and test stimuli was demonstrated in Experiment 2. In Experiment 3, 7-month-olds did not form a category of bird when habituated to prototypes. These findings constitute independent evidence for the existence of a linguistically relevant nonlinguistic category prior to the onset of word comprehension. Moreover, formation of prelinguistic categories appears to be facilitated by exposure to prototypes. Such goodness-of-exemplar effects suggest a structural similarity between infants' prelinguistic categories and early semantic categories. Finally, nonlinguistic categorization of natural basic-level objects, as represented in line drawings, appears to emerge between 0;7 and 0;9.

Considerable interest has been generated concerning linguistic and cognitive factors influencing the onset of early combinatorial speech. The present diary study provides evidence that, for some children, the transition between the single-word and two-word stages may be governed by phonological constraints. The presence of a phonological selection strategy and consonant harmony rule in one child's developing phonological system is described. Evidence is presented suggesting that this consonant harmony constraint operated across morpheme boundaries. This had the effect not only of delaying the onset of two-word utterances, but also of influencing the selection of words that could occur in word combinations. The implications of these findings for explaining individual variation in the transition from single-word to combinatorial speech are discussed.

Two young children were studied from the period when their expressive lexicons were approximately 30 words until they showed productive two-word positional patterns in their speech. Word combinations meeting the criteria for positional productive, positional associative and groping patterns were identified and the period during which the words appearing in these patterns were acquired was then determined. Words used in positional productive patterns had generally emerged in the children's speech before those used in associative or groping patterns. When several words that could play a particular semantic role (e.g. actor) were already well established in the child's lexicon, positional productive patterns that were somewhat broader in scope appeared as early as lexically based patterns.

The ability of children aged 0;1 to 2;6 to initiate and maintain topics of conversation is explored using videotaped data of mother–child interaction collected at home. An analysis of both verbal and non-verbal behaviours suggests that initially children attract attention exclusively to themselves as topics of conversation. The emergence of manipulative skills from 0; 5 and the development of deictic gestures from around the end of the first year facilitate the initiation of topics concerned with items in the physical environment. Finally, with the development of language, reference to intangibles becomes possible. In maintaining topics, children are initially capable of extended sequences only within the context of routines, but by 2;6 are able to maintain coherent topics independently. The implications of the analysis presented for understanding the role of prelinguistic communication in language development are discussed against the background of a modular framework.

This study provides longitudinal observations of young children's behaviours while viewing television in their own homes, over a time when the children were actively involved in the process of language acquisition. Sixteen children were observed for a period ranging from 0; 6 to 0;8. At the beginning, their ages ranged from 0; 6.15 to 5.15; at the end, from 1; 2.15 to 3;0. The observations yielded documentation of an overwhelming and consistent occurrence of language-related behaviours among children and parents in the viewing situation. The categories of child and adult talk are reported, with description and examples of each category. The categories are compared with those reported for parent–child interactions outside the viewing experience, – in particular joint book-reading. A model of television as a talking picture book is proposed. It is argued that television has the potential to serve as a facilitator of children's language acquisition.

The conclusion that information regarding the grammatically of children's speech is unavailable in parental input has recently been challenged (Moerk 1983 a, b, Hirsh-Pasek, Treiman & Schneiderman 1984). The present study expanded on this research by broadening the definition of ‘negative feedback’ and by describing individual styles of mother–child dialogues. The purpose was to investigate whether mothers of four 2-year-old children responded differentially to their children's well-formed or ill-formed utterances with explicit and implicit feedback. The middle-class, English-speaking, mother–child dyads were recorded in a naturalistic context at home during play and eating activities. Explicit and implicit feedback were different in terms of the proportion of responses available to the child and their relation to well-formed and ill-formed utterances. The style of response was similar for most analyses across the four mothers.

With the expectation that an examination of language between toddler twins in their home environment would reveal characteristics unique to the subjects' twin status, 31 hours of crib-talk between identical twin girls and diary records of their speech were examined. It was found that the subjects developed conventional syntax and vocabulary, but adapted them in ways which appropriately expressed their twin status. Three salient examplesinclude their use of a double name for themselves as a team, their use of singular verbs in reference to themselves together, and their use of the singular pronoun me in pronominal reference to themselves as a team.

Two groups of 3-year-old children (3:0–3;6 and 3;6–4;0) observed two actions of a toy. In one condition an older partner was absent while the subject watched both of the toy actions (fully ignorant partner), whereas in the other condition the partner witnessed one of the two actions together with the subject (partially ignorant partner). When asked about the toy's actions by their partially ignorant partner both age groups adjusted their answers to their partner's ignorance and mentioned only that action which was new to their partner. However, in their answers to their fully ignorant partner the younger children tended to provide insufficient information by mentioning only one instead of both actions.

Diary studies of English, Hebrew and Portuguese have led to debate on whether there is directionality in children's transitivity errors – that is, whether children are as likely to coin intransitives from transitives (*Bert knocked down) as they are transitives from intransitives (*I falled my cup). The judgements made by 3- and 4-year-olds showed a strong bias in favour of innovative transitives in English. It is argued that this bias results from children's preference for prototypical, highly transitive descriptions of events.

In two experiments, the early acquisition of spatial adjectives is examined. In Experiment 1, 3- to 4-year-old and 4- to 5-year-old English children were tested for their comprehension of big, tall and long. In general, comprehension of all three adjectives improved with age, but in confirmation of Maratsos (1973) there was a sharp increase with age in one particular type of error: when asked to select the bigger of two objects, older children frequently chose the taller but smaller member of the pair. Further analysis showed that those older children who understood the word tall were especially likely to make this error. In Experiment 2, Dutch children of the same age were tested for their comprehension of groot (meaning ‘big’) and lang (meaning both ‘tall’ and ‘long’). Dutch children were also prone to choose the taller of two objects when asked to point to the bigger one, although Dutch does not possess a spatial adjective such as tall that refers exclusively to the vertical dimension. The implications of the findings for the acquisition of spatial adjectives, and for theories of semantic development are discussed.

This study traces the development of predicate use for genre and cohesion in the narratives of children aged 2 to 5, examining predicate structures and types and their linkages via three types of parallelism and by means of explicit connectives. After age 2, bivalent (transitive) active verbs were dominant; semantically, verbs of the DO and then GO categories dominated until age 5, when BE verbs ranked second. The dominant type of parallelism was reiteration of grammatical structure alone; reiteration of both predicate structure and lexical content decreased with age. Concerning connectives, 2-year-olds used the smallest number – primarily ‘and’ – while 5-year-olds used the greatest variety. However, by age 5, children used parallelism as the second most common connective device after ‘and’.

The distribution of a number of syntactic structures in the speech output of 102 Israeli preschoolers was examined. Findings on the proportion of grammatically analysable clauses, the patterning of word order in Hebrew child language, and the emergence of syntactic connectedness through coordination and subordination of clauses are reported. Our analysis reveals that while in some areas there are clearly age-related differences among preschool children, other types of syntactic patternings exhibit a stable behaviour. We refer to the importance of integrating findings for a wide variety of seemingly unrelated syntactic constructions across different discourse modes. We also claim that complex interactions between structural, semantic and pragmatic factors underlie the child's acquisition of syntax.

This article reports an experimental investigation of the influence of linguistic factors on linguistic performance. The factors studied were interpretive complexity and surface length; they were expected to affect performance differentially, depending on the demands of the task. The stimulus sentences were three temporal adverbial structures wherein sentences high in interpretive complexity were low in surface length and vice versa. The experiment presented a toy-moving and an imitation task to children aged 3;6–6;0. The results show an interaction between type of linguistic complexity and type of linguistic performance. Sentences high in interpretive complexity were the most difficult in the toy-moving task and the easiest in the imitation task, and vice versa. The experiments suggest that different abilities are tapped by imitation and toy-moving tasks.

Recent work by Lust and others has led to the prediction that children acquiring left-branching languages will exhibit a preference for backward patterns of anaphora. In this paper, we test this prediction against data from Korean and Japanese and show it to be false. An alternative hypothesis proposing a preference for forward patterns of anaphora is outlined and possible explanations for earlier experimental results supporting Lust's prediction are considered.