The goals of this study were to analyze the growth and stability of vocabulary, mean length of the three longest utterances (MLLUw), and sentence complexity in European Portuguese-speaking children aged 1;4–2;6, to explore differences in growth as a function of personal and family-related variables, and to investigate the inter-relationships among the three language dimensions. Fifty-one European Portuguese-speaking toddlers were longitudinally assessed at 1;4, 1;9, 2;1, and 2;6, through parent reports. Exponential growth models best described acquisition patterns during this period, but the vocabulary growth accelerated across the full age-range, whereas the growth of grammar dimensions accelerated mainly after 1;9. High variability was observed in the scores, but the toddlers’ relative positions were mostly stable over time. Gender approached significance as a predictor of vocabulary growth. Maternal educational level did not predict the growth of any of the three language dimensions. Both vocabulary and MLLUw predicted sentence complexity.

When learning their first language, children develop strategies for assigning semantic roles to sentence structures, depending on morphosyntactic cues such as case and word order. Traditionally, comprehension experiments have presented transitive clauses in isolation, and cross-linguistically children have been found to misinterpret object-first constructions by following a word-order strategy (Chan, Lieven & Tomasello, 2009; Dittmar, Abbot-Smith, Lieven & Tomasello, 2008; Hakuta, 1982; McDonald, 1989; Slobin & Bever, 1982). In an act-out study, we replicated this finding with Danish preschoolers. However, object-first clauses may be context-sensitive structures, which are infelicitous in isolation. In a second act-out study we presented OVS clauses in supportive and unsupportive discourse contexts and in isolation and found that five- to six-year-olds' OVS comprehension was enhanced in discourse-pragmatically felicitous contexts. Our results extend previous findings of preschoolers' sensitivity to discourse-contextual cues in sentence comprehension (Hurewitz, 2001; Song & Fisher, 2005) to the basic task of assigning agent and patient roles.

Mothers have been found to respond differently to grammatical and ungrammatical utterances in young children's language. However, parents indicate that they are conscious only of responding to communicative aspects of their children's speech, not grammar. Further, researchers have looked to the understandability of utterances to explain the effects of grammaticality on maternal responses. The present study addressed the question of whether it is actually grammatical form that mothers respond to, or whether it is ambiguity in the communicative functions of children's utterances. Three mother-child dyads were videotaped in a free play setting when the children were 2;0 and 3;0. Children's spontaneous comprehensible utterances were rated for grammaticality and ambiguity of function, and mothers' responses to them were noted. Results indicated that mothers responded differentially to both the ambiguity and grammaticality of children's utterances, and that these two factors had some degree of independence in their effects on mothers' responses.

Rosemarie Tracy is leaving the Editorial Team. I would like to thank her sincerely for the hard work and care that she has put into her work as Associate Editor over the last three years and to welcome Clifton Pye of the University of Kansas and Paul Fletcher of the University of Hong Kong as new Associate Editors.

This study investigated the associations between maternal depression when infants were 3 to 11 months old (M = 6 months), and positive parenting behaviors when children were between 12 and 22 months (M = 17 months) and the home language environment assessed when children were 18 to 28 months old (M = 23.5 months) in a sample of 29 low-income mother–child dyads. After controlling for maternal education, only teaching behaviors remained a moderate and significant predictor of adult word counts. Observed teaching behaviors significantly predicted conversational turns and marginally predicted child vocalizations; effects sizes were small. Encouraging behaviors were a small and significant predictor of conversational turns and a marginally significant predictor of adult word counts. Maternal depression was a moderate and significant predictor of children's vocal productivity scores and a small, marginal predictor of conversational turns. These findings have important implications for parenting and children's language outcomes.

The current study investigates how bilingual children encode and produce morphologically complex words. We employed a silent-production-plus-delayed-vocalization paradigm in which event-related brain potentials (ERPs) were recorded during silent encoding of inflected words which were subsequently cued to be overtly produced. The bilingual children's spoken responses and their ERPs were compared to previous datasets from monolingual children on the same task. We found an enhanced negativity for regular relative to irregular forms during silent production in both bilingual children's languages, replicating the ERP effect previously obtained from monolingual children. Nevertheless, the bilingual children produced more morphological errors (viz. over-regularizations) than monolingual children. We conclude that mechanisms of morphological encoding (as measured by ERPs) are parallel for bilingual and monolingual children, and that the increased over-regularization rates are due to their reduced exposure to each of the two languages (relative to monolingual children).

This study investigated how forty-six mothers modified their talk about familiar and unfamiliar nouns and verbs when interacting with their children with Down Syndrome (DS), language impairment (LI), or typical development (TD). Children (MLUs < 2·7) were group-matched on expressive vocabulary size. Mother–child dyads were recorded playing with toy animals (noun task) and action boxes (verb task). Mothers of children with DS used shorter utterances and more verb labels in salient positions than the other two groups. All mothers produced unfamiliar target nouns in short utterances, in utterance-final position, and with the referent perceptually available. Mothers also talked more about familiar nouns and verbs and labelled them more often and more consistently. These findings suggest that mothers of children in the early period of language development fine-tune their input in ways that reflect their children's vocabulary knowledge, but do so differently for nouns and verbs.

The present study investigated the expression of the part–whole semantic relation by children 3 to 12 years of age. Controlling both task format (structured vs. open-ended) and dimensions associated with experimental stimuli (part-word vs. part-object; known whole vs. unknown whole), the verbal responses of two age groups of children were analysed. While results revealed the part–whole semantic relation expressible by even the youngest children, age-group comparisons indicated that the older children preferred its use significantly more often. The part–whole semantic relation was also observed to take several linguistic forms (partitive, spatial, possessive), the selection of which varied as a function of age, task format, and type of experimental stimuli. Findings are discussed relative to issues concerning research methodology, the elicitation and assessment of children's semantic knowledge, and cognitive developmental theory.

Edwards (1992c) concerns data and data use rather than manuals. It presents principles to facilitate reliable archive research in an imperfect world. MacWhinney & Snow (1992) endorse the principles but disagree on important details, discussed in this response. M&S underrate the impact of corpus inconsistencies on substantive conclusions. Since acquisition research concerns events which often trickle in a few at a time, main findings often involve a handful of examples, so overlooking a single early variant can seriously skew results. Until archives become perfect, if they do, type-token listings can help in identifying variants before computer search and avoiding this hazard.

Young children are skilled language learners. They apply their skills to the language input they receive from their parents and, in this way, derive patterns that are statistically related to their input. But being an excellent statistical learner does not explain why children who are not exposed to usable linguistic input nevertheless communicate using systems containing the fundamental properties of language. Nor does it explain why learners sometimes alter the linguistic input to which they are exposed (input from either a natural or an artificial language). These observations suggest that children are prepared to learn language. Our task now, as it was in 1974, is to figure out what they are prepared with – to identify properties of language that are relatively easy to learn, the resilient properties, as well as properties of language that are more difficult to learn, the fragile properties. The new tools and paradigms for describing and explaining language learning that have been introduced into the field since 1974 offer great promise for accomplishing this task.

Research is reported which investigated the ability of 4-month-old hearing infants to discriminate between gestures, derived from American Sign Language (ASL), that differ solely in terms of contrasts along underlying movement dimensions. Using an habituation–dishabituation task, it is shown that young infants can make such discriminations for global movement contrasts as well as contrasts along a single movement dimension. Thus, at four months, infants possess certain prerequisite perceptual abilities for the analysis of the signs of a visually specified language. Partial failure to dishabituate to another movement contrast, however, suggests that readiness to utilize the information in gestural events may vary depending on the movement in question. Results are contrasted to infant speech perception findings and implications for further research in the development of sign perception are discussed.

Schaeffer (1997, 2000) argues that children lack knowledge of specificity because Dutch children omit determiners and fail to scramble pronouns. Avrutin & Brun (2001), however, find that Russian children place arguments correctly according to whether they are specific or non-specific. This paper investigates object agreement and specificity in early Swahili. Object agreement in Swahili is obligatory when the object is specific, but is prohibited when the object is non-specific. Analysis of naturalistic data from four Swahili-speaking children (1;8–3;2) reveals that children overwhelmingly provide object agreement in obligatory contexts (when the object is a personal name, is topicalized, or refers to first/second person). The supply of object agreement cannot be due to a general strategy of overusing agreement, since object agreement does not occur in prohibited contexts such as intransitive clauses. I conclude that object agreement and knowledge of specificity are acquired by Swahili children before the age of two years.

The relationship between affix processing and linguistic systems was evaluated through an analysis of prefixation and suffixation in the tense-aspect and locative systems of child Polish. For six children ranging in age from 1; 7 to 2; 6, the distinction between imperfective and perfective aspect was made more frequently by prefixation than by suffixation. Prefixation was found to be just as productive in the specification of locative distinctions as aspectual distinctions. We found no bias in affix processing which might have favoured suffixation, and no interaction of linguistic systems with affix processing. Furthermore, an inter-language comparison confirmed these intralanguage findings. Finally, we argued that affix processing involves a parallel analysis of patterns of stored information providing the motivation for selective attention.

This paper concerns the development of semi-modal want/want to, and modals may, can and could in two Trinidadian children, whose Verb Phrase development was studied in naturalistic settings, between the ages of 2;3 and 4;1, and 2;4 and 4;9. The similarities and differences in development between the two are important for underlining a number of key factors in the acquisition process. Accepting the salience of requests/demands in early child language, the study draws attention to the child's propensity for using the means most readily available to him/her in the input, for expression of this function. Additionally, there is evidence of the child's ability to make stylistic discriminations at a very early age and of the propensity for making semantic distinctions among forms. The study indicates that work on the development of grammatical features is incomplete without consideration of sociolinguistic aspects of usage as integral to grammatical acquisition from the outset.

The entry into language via first words and, the acquisition of word meanings is considered from the perspective of publications in the Journal of Child Language over the past forty years. Problems in achieving word meanings include the disparate and sparse concepts available to the child from past prelanguage experience. Variability in beginning word learning and in its progress along a number of dimensions suggests the problems that children may encounter, as well as the strategies and styles they adopt to make progress. Social context and adult practices are vitally involved in the success of this process. Whereas much headway has been made over the past decades, much remains to be revealed through dynamic systems theory and developmental semiotic analyses, as well as laboratory research aimed at social context conditions.

Words have meanings vastly undetermined by the contexts in which they occur. Their acquisition therefore presents formidable problems of induction. Lila Gleitman and colleagues have advocated for one part of a solution: indirect evidence for a word’s meaning may come from its syntactic distribution, via syntactic bootstrapping. But while formal theories argue for principled links between meaning and syntax, actual syntactic evidence about meaning is noisy and highly abstract. This paper examines the role that syntactic bootstrapping can play in learning modal and attitude verb meanings, for which the physical context is especially uninformative. I argue that abstract syntactic classifications are useful to the child, but that something further is both necessary and available. I examine how pragmatic and syntactic cues can combine in mutually constraining ways to help learners infer attitude meanings, but need to be supplemented by semantic information from the lexical context in the case of modals.

The validity of the Language ENvironment Analysis (LENA) System was evaluated for Dutch. 216 5-min samples (six samples per age per child) were selected from daylong recordings at 5, 10 and 14 months of age of native Dutch-speaking younger siblings of children with autism spectrum disorder (N = 6) and of typically developing children (N = 6). Two native Dutch-speaking coders counted the amount of adult words (AWC), child vocalisations (CVC) and conversational turns (CT). Consequently, correlations between LENA and human estimates were explored. Correlations were high for AWC at all ages (r = .73 to .81). Regarding CVC, estimates were moderately correlated at 5 months (r = .57) but the correlation decreased at 10 (r = .37) and 14 months (r = .14). Correlations for CT were low at all ages (r = .19 to .28). Lastly, correlations were not influenced by the risk status of the children.

Previous research on the effects of word-level factors on lexical acquisition has shown that frequency and concreteness are most important. Here, we investigate CDI data from 1,030 Dutch children, collected with the short form of the Dutch CDI, to address (i) how word-level factors predict lexical acquisition, once child-level factors are controlled, (ii) whether effects of these word-level factors vary with word class and age, and (iii) whether any interactions with age are due to differences in receptive vocabulary. Mixed-effects regressions yielded effects of frequency and concreteness, but not of word class and phonological factors (e.g., word length, neighborhood density). The effect of frequency was stronger for nouns than predicates. The effects of frequency and concreteness decreased with age, and were not explained by differences in vocabulary knowledge. These findings extend earlier results to Dutch, and indicate that effects of age are not due to increases in vocabulary knowledge.

Previous studies on bilingual children found intact tonal development at the initial stages of interaction between Cantonese and English in successive bilingual children, whereas children exposed to both languages from birth have not been studied in this regard. We examined the production of Cantonese tones by five simultaneous bilingual children longitudinally at 2;0 and 2;6, and compared them with age-matched monolingual children using auditory analysis. Our results showed that some bilingual children had a delay at 2;0, compared to their monolingual peers. Some bilingual children also exhibited a ‘high–low’ template in their production, resembling the pitch pattern of English trochaic words. These findings suggest a possible early interaction of the Cantonese and English prosodic systems in which bilingual children adopted the English stress pattern in Cantonese production. The time-point along the trajectory of phonological development is important in modulating whether cross-linguistic transfer can be observed.

This study examined the development of evaluative language in preschoolers’ oral fictional narratives using a storytelling/story-acting practice where children told stories to and for their friends. Evaluative language orients the audience to the teller's cognitive and emotional engagement with a story's events and characters, and we hypothesized that this STSA context might yield new information about the early development of this language, prior to elementary school. We analyzed 60 stories: the first and last story told by 10 children in each of three preschool classrooms (3-, 4-, and 5-year-old classes) that used STSA throughout the school year. Stories were coded for evaluative expressions and evidential expressions. Five-year-olds used significantly more evaluative language than did 3-year-olds, and children at all ages used significantly more evaluative language at the end than at the beginning of the year. The number of stories told throughout the year explained unique variance in children's evaluative language growth.