This research explores the role of phonotactic probability in two-year-olds' production of coda consonants. Twenty-nine children were asked to repeat CVC non-words that were used as labels for pictures of imaginary animals. The CVC non-words were controlled for their phonotactic probabilities, neighbourhood densities, word-likelihood ratings, and contained the identical coda across low and high phonotactic probability pairs. This allowed for comparisons of children's productions of the same coda consonant in low and high phonotactic probability environments. Children were significantly more likely to produce the same coda in high phonotactic probability non-words than in low phonotactic probability non-words. These results are consistent with the hypothesis that phonotactic probability is a predictor of coda production in English. Moreover, this finding provides further evidence for the role of the input and distribution of sound patterns in the ambient language as a basis for phonological acquisition.

The Editors would like to register their great sadness at the tragically early death of our colleague, Elizabeth Bates. The loss of her empirical breadth, her theoretical engagement and her sheer energy and enthusiasm for the fundamental questions that engage us all, will leave a huge gap.

Ann Peters and Dan Dinnsen are leaving our editorial team. Ann Peters has served as an Associate Editor for 8 years and Dan Dinnsen for 5 years. In both cases, their contribution to the Journal has been invaluable and on behalf of the Editorial Team, of those who submit papers to the Journal and of those who read it, I would like to thank them for their collegiality and for all their extremely careful and hard work.

In two experiments we tested the hypothesis that children have a basic problem in mastering the attributive relation because it involves a two-step logical–semantic integration process of the head-noun and the attributive adjective. Hebrew-speaking children were asked to interpret highly familiar adjective–noun combinations by selecting a photo that depicted the correct referent. In Experiment 1 there were four choices for each adjective–noun pair: correct object/correct property, correct object/wrong property, wrong object/correct property, wrong object/wrong property. 170 children (1;6–4;4) participated. Analyses of errors and spontaneous self-corrections indicated that children initially ignored the adjective and based their responses only on the noun. In Experiment 2, in addition to the 4-choice condition, there were two simpler conditions with only two choices: the correct object/correct property, and either the correct object/wrong property, or the wrong object/correct property. 30 children (1;9–4;11) were tested. The children, and in particular the lowest-scoring third of the sample, did significantly better in the 2-pictures conditions. The results suggest that young children do possess a basic adjective vocabulary and can use it in simple discriminations, but have a considerable difficulty in integrating the information furnished by the adjective with information furnished by the noun.

The acquisition of case and gender marking on the definite and indefinite article was studied in a sample of 6 normally-hearing children and 9 children with cochlear implants. Longitudinal spontaneous speech data are used. Children were matched by MLU, with 4 MLU levels: 1·8, 2·8, 3·6, 4·8. Age ranges for normally-hearing children were 1;4 to 3;8 and for children with cochlear implants 1;8 to 7;0. Frequencies of correctly marked article forms increased over MLU but less so in the hearing-impaired group. In both groups error rates were high. However, error patterns were different. In normally-hearing children errors of case predominated, in hearing-impaired children errors of gender and omission. Error patterns suggest that in normally-hearing children syntactic categorization interacts with input frequency and low discriminability of article forms. In the hearing-impaired group the article system is less advanced, despite higher frequencies of definite articles in adult speech. The predominance of article omission is discussed in terms of persisting perceptual problems or a working memory deficit.

The ability to understand references to the absent enables conversation to move beyond the here-and-now to matters distant in both space and time. Such understanding requires appreciating the relation between language and communicative intent: one must recognize speakers' intentions to use language to converge on a shared conversational focus that is at least somewhat independent of the current context. Despite its centrality to language development, the emergence of absent reference understanding has received little systematic attention. The present research investigated the responses of 60 infants aged 1;0 to 2;6 to a researcher talking about both present and absent caregivers. When infants aged 1;3 and older heard talk about absent caregivers they displayed a complex of nonverbal communicative responses that were divergent from their responses to talk about a present person. Infants aged 2;0 and older provided responses indicating understanding of absent reference. The findings suggest that by 1;3 infants may have at least a tacit appreciation of language as a device for coordinating conversational focus, and hint at increased sophistication in infants' absent reference comprehension skills at 2;0.

Research undertaken to date suggests that important developments in the understanding and use of intonation may take place after the age of 5;0. The present study aims to provide a more comprehensive account of these developments. A specially designed battery of prosodic tasks was administered to four groups of thirty children, from London (U.K.), with mean ages of 5;6, 8;7, 10;10 and 13;9. The tasks tap comprehension and production of functional aspects of intonation, in four communicative areas: CHUNKING (i.e. prosodic phrasing), AFFECT, INTERACTION and FOCUS. Results indicate that there is considerable variability among children within each age band on most tasks. The ability to produce intonation functionally is largely established in five-year-olds, though some specific functional contrasts are not mastered until C.A. 8;7. Aspects of intonation comprehension continue to develop up to C.A. 10;10, correlating with measures of expressive and receptive language development.

Williams syndrome (WS) is often cited as the prime example within developmental disorders of the dissociation of language from other cognitive skills, particularly from visuo-motor skills. This claim has been responsible for the challenges posed by this population to cognitive theories and to models of language acquisition. Two Hebrew-speaking children with WS were followed longitudinally for 18 months, from the first occurrences of two word combinations. Y was 3;9–5;3 and BT was 4;2–5;8 during data collection. Both children had an MLU of 1·8–2·8. The children's linguistic profiles were compared to the profiles of typically-developing (TD) children of similar MLU as well as to the profiles of 11 children with a variety of neurodevelopmental disorders (ND), matched on MLU. The profiles exhibited by the children with WS throughout the period of the study differed from the profiles seen in both control groups.

The purpose of this research was to show how the syntactic and semantic components of the tense–aspect system interact during the acquisition process. Our methodology involved: (1) identifying predicates, (2) finding the initial occurrence of their tense–aspect morphology, and (3) observing the emergence of contrasts. Six children learning Polish and six children learning English, found in the CHILDES archives, were investigated. The average starting age of the children learning English was 1;11, and 1;8 for the children learning Polish. In the first analysis, we traced the same 12 verbs in both languages, and in the second analysis, we contrasted the acquisition patterns for a set of telic versus atelic predicates. We tracked the verbs/predicates from the starting age to 4;11 or the child's final transcript. In English, progressive aspect is the marked form, and in Polish, perfective aspect is the marked form. This typological distinction has a significant effect of the acquisition patterns in the two languages. We argue that children acquire a multi-dimensional system having deictic relations as one of the basic dimensions. This process can be best understood within a functional theoretical framework having a well-defined syntactic–semantic interface.

The present study investigates the performance of 96 Cantonese-speaking three- to five-year-old preschoolers on three false belief tasks – a deceptive object, a change of location, and an unexpected contents task encompassing a variety of task factors. Most importantly, the research examines the possibility that false belief performance depends on specific linguistic factors such as the type of verb used in the test question – an explicitly false vs. a neutral belief verb. Cantonese was chosen as particularly useful for examining this question because it explicitly codes belief status as either neutral (nam5) or false (ji5wai4), and because it offers additional linguistic and cultural contrasts to research conducted on false belief with children learning English and other Indo-European languages. As expected, a strong age effect was found, as well as a significant advantage for children who received the explicit false belief (ji5wai4) wording and for those who were asked to explain rather than predict the protagonist's actions. Interestingly, there was also a strong task difference with children performing better on the deceptive object task than on the other two false belief tasks. We argue that these results point both to universal trajectories in theory of mind development and to interesting, but localized, effects of language and culture on children's false belief understanding.

When English-speaking two-year-olds begin producing polysyllabic words, they often omit unstressed syllables that precede syllables with primary stress (Allen & Hawkins, 1980; Klein, 1981; Gerken, 1994a). One proposed mechanism for these omissions is that children omit syllables at a phonological level, due to prosodic constraints that act on outputs. Under such accounts, it has been largely assumed that these syllables are simply missing, or deleted, from children's outputs. The present research consists of a pair of experiments that tested this assumption by investigating the acoustic properties of utterances manifesting or lacking weak initial syllable omissions. In the two experiments, 33 two-year-old children were asked to imitate sentences like ‘He kissed Lucinda’ (often reduced as expected to a disyllabic trochaic form, e.g. ‘He kissed _cinda’) and ‘He kissed Cindy’. Durations of each child's imitations were measured from the onset of the verb to the onset of the name, for each pair of sentences containing the reduced or unreduced disyllabic forms, for example, ‘kissed _cinda’ vs. ‘kissed Cindy’. Our results yielded a significantly longer duration for the verb-onset to name-onset portion of sentences containing reduced ‘_cinda’-type names than for sentences with ‘Cindy’-type names. This finding provides evidence that children do not completely delete weak syllables. Rather, the data from the phonetic analysis indicate that some prosodic trace exists of the omitted syllable.

A set of tri-zygotic quadruplets, three girls and one boy, participated in weekly observations from 1;2 to 1;10 (years;months), a period of transition from prelinguistic gesture to 50 words. In the study, one girl served as a genetic mate to her identical twin and a biological risk mate to her fraternal sister. The biological risk mates achieved milestones in lexical development at similar times; however, the genetic mates demonstrated more similarities in pattern of lexical development and in the modality of their word productions. Degree of similarity changed over the observation period. Imposed upon the natural experiment was a within-subject manipulation of the social environment: The experimenters modelled a core vocabulary via the gesture+verbal modalities to the children during each visit. The modelling resulted in increased rates of word learning for three of the children; the child with the greatest biological risk, the boy, derived the greatest benefit. The findings provide unique support for a dynamic, multi-factorial model of lexical development involving the interaction of genetics, the biological environment and the social environment. Furthermore, they illustrate the robustness of early lexical development in the face of biological risks.

This study examined parental report as a source of information about toddlers' productive vocabulary in 105 low-income families living in either urban or rural communities. Parental report using the MacArthur Communicative Development Inventory – Short Form (CDI) at child age 2;0 was compared to concurrent spontaneous speech measures and standardized language assessments, and the utility of each source of data for predicting receptive vocabulary at age 3;0 (Peabody Picture Vocabulary Test) was evaluated. Relations between language measures of interest and background variables such as maternal age, education, and race/ethnicity were also considered. Results showed that for the sample as a whole, parental report was moderately associated with other language measures at age 2;0 and accounted for unique variance in PPVT at age 3;0, controlling for child language skills derived from a standard cognitive assessment. However, predictive validity differed by community, being stronger in the rural than in the urban community. Implications of significant differences in background characteristics of mothers in the two sites are discussed.

The present article focused on two types of communicative intent (directing behaviour vs. eliciting talk) expressed by mothers and teenagers during everyday family interactions in Estonian, Finnish, and Swedish mono- and bicultural families. Three monocultural groups consisted of 17 Estonian, 19 Swedish, and 18 Finnish families living in their country of origin; two bicultural and bilingual groups consisted of 18 Estonian and 18 Finnish families residing in Sweden. All the children were between 9;0 and 13;0. The results revealed that the Estonian monocultural mothers were highly directive and direct: issuing behavioural directives most frequently and using the highest proportion of imperatives among all samples. Contrary to our expectations, the mothers who tended to be more concerned with controlling their children's behaviour also elicited conversation more frequently from teenagers by using a larger number of information requests. These requests seemed to serve as another form of attempted control over adolescents' behaviour – their communicative behaviour. The Swedish monocultural children were more active in controlling their mothers' behaviour than their counterparts, possibly illustrating the Swedish value of generational equality.

The paper examines two types of texts, personal experience narratives and expository discussions, dealing with the shared theme of interpersonal conflict. Both were produced by the same 80 subjects, participants in a crosslinguistic study on developing literacy: gradeschoolers aged 9;0 to 10;0, twelve-to-thirteen-year-old junior high school students, sixteen-to-seventeen-year-old high school students, and graduate-level university students. The study reported here aims to demonstrate that inter-genre differentiation is evident from an early age and is reflected by distinct forms of expression across different interlocking linguistic systems. In keeping with the focus on relations between linguistic forms and discourse functions that motivates our study, we further aim to show how particular grammatical elements can fulfil different discourse functions across development. To this end, we analysed several different lexical and morphosyntactic constructions in 160 Hebrew-language texts as diagnostic of inter-genre distinctiveness: subjectless constructions; verbless copular clauses; verb types and the temporal categories of verb tense and mood, including lexical expressions of modality in the two genres. Results show that narratives are clearly distinguished from expository texts along all these dimensions; these distinctions are evident from the youngest age group we considered; and with age, inter-genre differentiation emerges as more moderately dichotomous. We concluded from this that maturely proficient text construction is able to combine expository-type generalizations with narrative event-description and to intersperse narrative-type illustrative episodes with expository formulation of ideas.

In many areas of language acquisition, researchers have suggested that semantic generality plays an important role in determining the order of acquisition of particular lexical forms. However, generality is typically confounded with the effects of input frequency and it is therefore unclear to what extent semantic generality or input frequency determines the early acquisition of particular lexical items. The present study evaluates the relative influence of semantic status and properties of the input on the acquisition of verbs and their argument structures in the early speech of 9 English-speaking children from 2;0 to 3;0. The children's early verb utterances are examined with respect to (1) the order of acquisition of particular verbs in three different constructions, (2) the syntactic diversity of use of individual verbs, (3) the relative proportional use of semantically general verbs as a function of total verb use, and (4) their grammatical accuracy. The data suggest that although measures of semantic generality correlate with various measures of early verb use, once the effects of verb use in the input are removed, semantic generality is not a significant predictor of early verb use. The implications of these results for semantic-based theories of verb argument structure acquisition are discussed.

Although words have both denotative and connotative meanings, there has been little research on the child's acquisition of connotations. In large segments of written texts, connotations can be studied by examining word co-occurrences (collocations). Using this technique, corpus linguists have found, for example, that ‘happen’ has a negative connotation; it most often collocates with negative words (e.g. ‘accidents’, ‘something dreadful’). The current research is a case study of the use of the lemma ‘happen’. Adult production of ‘happen/happens/happening/happened’ was examined in 151 American English-speaking, adult–child dyads from the CHILDES database. Within these dyads, 35 children used ‘happen’ and its variants. Both adults and children were increasingly likely to use ‘happen’ to describe negative contexts as children's language progressed from MLUs around 1·00 to MLUs greater than 4·00. Results are consistent with usage-based theories of language that claim that the relative frequency of information in the input is critical to language learning.

There has been relatively little discussion in the field of child language acquisition about how best to sample from children's spontaneous speech, particularly with regard to quantitative issues. Here we provide quantitative information designed to help researchers make decisions about how best to sample children's speech for particular research questions (and/or how confident to be in existing analyses). We report theoretical analyses in which the major parameters are: (1) the frequency with which a phenomenon occurs in the real world, and (2) the temporal density with which a researcher samples the child's speech. We look at the influence of these two parameters in using spontaneous speech samples to estimate such things as: (a) the percentage of the real phenomenon actually captured, (b) the probability of capturing at least one target in any given sample, (c) the confidence we can have in estimating the frequency of occurrence of a target from a given sample, and (d) the estimated age of emergence of a target structure. In addition, we also report two empirical analyses of relatively infrequent child language phenomena, in which we sample in different ways from a relatively dense corpus (two children aged 2;0 to 3;0) and compare the different results obtained. Implications of these results for various issues in the study of child language acquisition are discussed.

We investigated infant precursors of low language scores in early childhood. The sample included 373 probands in 130 monozygotic (MZ) and 109 same-sex dizygotic (DZ) twin pairs in which at least one member of the pair scored in the lowest 15th percentile of a control sample on a general language factor derived from tester-administered tests at 4;6. From data at 2;0, 3;0 and 4;0 the antecedents of poor language performance at 4;6 for these probands were compared to 290 control children. As early as 2;0, language measures substantially predicted low-language status at 4;6, with predictions increasing at 3;0 and 4;0. Nonverbal cognitive development at 3;0 and 4;0 was nearly as predictive of low language at 4;6 as were the language measures. Behaviour problems were also significant predictors of low language status although the associations were only about half as strong. Bivariate genetic analyses indicated that these predictions are mediated by both genetic and shared environmental links.

In a longitudinal study, 17 parent–child dyads were observed during free-play when the children were 1;0, 1;6, and 2;0. Parents' labelling input in the verbal and gestural modalities was coded at each session, and parents completed a vocabulary checklist for their children at each visit. We analysed how the frequency of labelling in the verbal and gestural modalities changed across observation points and how changes in parental input related to children's vocabulary development. As a group, parents' verbal labelling remained constant across sessions, but gestural labelling declined at 2;0. However, there are notable individual differences in parental trajectories in both modalities. Parents whose verbal labelling frequency increased over time had children whose vocabulary grew more slowly than those whose labelling frequency decreased, remained constant, or peaked at 1;6. There were few systematic relations between patterns of parental gesturing and children's vocabulary development. Parents' verbal and gestural labelling patterns also appeared dissociable. However, parents' words and gestures were correlated when their children were 1;6, suggesting that gestures serve an important bootstrapping function at a critical point in children's vocabulary development.