Thai has imperfective aspectual morphemes that are not obligatory in usage, whereas English has obligatory grammaticized imperfective aspectual marking on the verb. Furthermore, Thai has verb final deictic-path verbs that form a closed class set. The current study investigated if obligatoriness of these grammatical categories in Thai and English affects the expression of co-occurring temporal events and actions depicted in three different short animations. Ten children aged four years, five years, six years and seven years, and ten adults as a comparison group from each of the two languages participated. English speakers explicitly expressed the ongoingness of the events more than Thai speakers, whereas Thai speakers expressed the entrance and exit of protagonists depicted in the animations significantly more than English speakers. These results support the notion that obligatory grammatical categories shape how Thai and English speakers express temporal events or actions.

Twenty-four infants were tested monthly for the production of imperative and declarative gestures between 0 ; 9 and 1 ; 3 and concurrent mother–infant free-play sessions were conducted at 0 ; 9, 1 ; 0 and 1 ; 3 (Carpenter, Nagell & Tomasello, 1998). Free-play transcripts were subsequently coded for maternal talk about mental states. Results revealed that the earlier infants produced imperative gestures, the more frequently their mothers made reference to the infants' own volitional states (want, try, need, etc.) at 1 ; 3. The same relation also emerged using maternal reports of their infants' gestural communication on a standard language development measure. These results indicate that mothers' talk about desires and intentions is linked to their infants' early developing communicative competence.

Before they are three years old, most children have started to build coherent discourse. This article focuses on one important linguistic device children have to learn: connectives. The main questions are: Do connectives emerge in a fixed order? And if so, how can this order be explained? In line with Bloom et al. (1980) we propose to explain similarities in the development in terms of cumulative cognitive complexity: complex relations are acquired later than simple ones. Following a cognitive approach to coherence relations, we expect positive relations to be acquired before negatives and additives before temporals and causals. We develop a multidimensional approach to the acquisition process in order to account for the variation among children. Hypotheses were tested by analyzing data from children aged 1 ; 5–5 ; 6 on the emergence of Dutch connectives. The multidimensional approach of cognitive complexity describes both the uniformity and the diversity in the developmental sequences of Dutch-speaking and English-speaking children.

Early prosodic development (f0 variation) was systematically measured in Mandarin-learning infants at the transition from babbling to producing first words. Spontaneous vocalizations of twenty-four infants aged 0 ; 7 to 1 ; 6 were recorded in 45-minute sessions. The speech production of twenty-four caregivers was also audio-recorded during caregiver–infant natural daily interactions at home. All recordings were transcribed using broad prosodic patterns. Analysis revealed four major findings: (1) falling f0 contours were more prominently produced than level and rising contours; (2) high prosodic patterns occurred more frequently than mid and low prosodic patterns; (3) these distribution patterns of f0 contours showed significant similarities in babbling and early words; and (4) these distribution patterns were also similar in infants' and their caregivers' data.

This study examines pragmatic differentiation in early trilingual development through a longitudinal analysis of language choice in a developing Tagalog–Spanish–English trilingual child. The child's patterns of language choice with different language users are analyzed at age 1 ; 10 and 2 ; 4 to examine: (1) whether evidence for pragmatic differentiation can be found even before age two and in simultaneous interactions with distinct language users; (2) whether lexical gaps determine the child's choice of one language over another; and (3) whether her patterns of language choice are affected by the interlocutors language use and their responses to mixing. The results indicate that the child was capable of selecting the appropriate language according to the interlocutors' language from the earliest sessions. However, switches to inappropriate languages were common due to vocabulary gaps, the interlocutors' acceptance of mixing and the possibilities determined by the existence of multiple lexical resources and multiple language users.

The aim of this study was to examine what four-year-old children repair in their speech. For this purpose, conversational self-repairs (N=316) made by two typically developing Finnish-speaking children (aged 4 ; 8 and 4 ; 11) were examined. The data comprised eight hours of natural interactions videotaped at the children's homes. The tapes were analyzed using conversation analysis. The children made phonological, morphological, syntactic, lexical and non-linguistic self-repairs, and also inserted additional material into their utterances. Finnish-speaking children made more syntactic and fewer morphological self-repairs than the previous research on English-speaking children suggests. Furthermore, most self-repairs were found in talk during pretend play. In designing and engaging in such play, the children skilfully used self-repair to match their talk to meet the requirements of different interactive activities and co-participants. Finally, contextual analysis of children's self-repairs showed that these were also socially motivated, and not just related to slips or errors in speech.

The present study determined whether parenting style, defined by control strategies varying in power-assertion mediated the established relation between maternal language usage (grammar and semantics) and child language (grammar, semantics and pragmatics) during toddlerhood (n=60). Based upon their use of control strategies mothers were categorized into continuum-of-control groups (i.e. high guidance (HG), high control (HC) or high negative control (HNC)). Mothers in the high negative control group, who characteristically used high levels of prohibitions and commands, had children who performed relatively poorly overall on the language measures (i.e. MLU, number of bound morphemes, number of different words and use of language functions). In contrast, children of mothers in the HG and HC groups exhibited more advanced language usage overall. The relation between maternal and child language usage was mediated by parenting style for child pragmatics and partially for child grammar.

This study explores different frequency effects on children's interpretations of novel noun–noun compounds (e.g. egg bag as ‘bag FOR eggs’). We investigated whether four- to five-year-olds and adults use their knowledge of related compounds and their modifier–head relations (e.g. sandwich bag (FOR) or egg white (PART-OF)) when explaining the meaning of novel compounds and/or whether they are affected by overall frequency of modifier–head relations in their vocabulary. Children's interpretations were affected by their experience with relations in compounds with the same head, but not by overall relation frequency. Adults' interpretations were affected by their experience with relations in compounds with the same modifier, suggesting that children and adults use similar but different knowledge to interpret compounds. Furthermore, only children's interpretations revealed an overuse of visually perceivable relations.

The study examines prosodic characteristics of Hebrew speech directed to children between 0 ; 9–3 ; 0 years, based on longitudinal samples of 228,946 tokens (8,075 types). The distribution of prosodic patterns – the number of syllables and stress patterns – is analyzed across three lexical categories, distinguishing not only between open- and closed-class items, but also between these two categories and a third, innovative, class, referred to as between-class items. Results indicate that Hebrew CDS consists mainly of mono- and bisyllabic words, with differences between lexical categories; and that the most common stress pattern is word-final, with parallel distributions found for all categories. Additional analyses showed that verbs take word-final stress, but nouns are both trochaic and iambic. Finally, a developmental analysis indicates a significant increase in the number of iambic words in CDS. These findings have clear implications regarding the use of prosody for word segmentation and assignment of lexical class in infancy.

In this paper we propose a method for characterizing development in large longitudinal corpora. The method has the following three features: (i) it suggests how to represent development without assuming predefined stages; (ii) it includes caregiver speech/child-directed speech; (iii) it uses statistical association measures for investigating co-occurrence data. We exemplify the implementation of these proposals with data on the acquisition of the patterning of tense and grammatical aspect of four Russian children. The method, however, is suitable for a wide range of other acquisition questions as well.

This study examines the perfective past tense of Greek in an elicited production and an acceptability judgment task testing 35 adult native speakers and 154 children in six age groups (age range: 3 ; 5 to 8 ; 5) on both existing and novel verb stimuli. We found a striking contrast between sigmatic and non-sigmatic perfective past tense forms. Sigmatic forms (which have a segmentable perfective affix (-s-) in Greek) were widely generalized to different kinds of novel verbs in both children and adults and were overgeneralized to existing non-sigmatic verbs in children's productions. By contrast, non-sigmatic forms were only extended to novel verbs that were similar to existing non-sigmatic verbs, and overapplications of non-sigmatic forms to existing sigmatic verbs were extremely rare. We argue that these findings are consistent with dual-mechanism accounts of morphology.

English-speaking children make pronoun case errors producing utterances where accusative pronouns are used in nominative contexts (me do it). We investigate whether complex utterances in the input (Let me do it) might explain the origin of these errors. Longitudinal naturalistic data from seventeen English-speaking two- to four-year-olds was searched for 1psg accusative-for-nominative case errors and for all 1psg preverbal pronominal contexts. Their caregivers' data was also searched for 1psg preverbal pronominal contexts. The data show that the children's proportional use of me-for-I errors correlated with their caregivers' proportional use of me in 1psg preverbal contexts. Furthermore, the verbs that children produced in me-error utterances appeared in complex sentences containing me in the input more often than verbs that did not appear in me-for-I errors in the children's speech. These findings are discussed in the context of current explanations for children's case marking errors.

Verbs are harder to learn than nouns in English and in many other languages, but are relatively easy to learn in Chinese. This paper evaluates one potential explanation for these findings by examining the construct of imageability, or the ability of a word to produce a mental image. Chinese adults rated the imageability of Chinese words from the Chinese Communicative Development Inventory (Tardif et al., in press). Imageability ratings were a reliable predictor of age of acquisition in Chinese for both nouns and verbs. Furthermore, whereas early Chinese and English nouns do not differ in imageability, verbs receive higher imageability ratings in Chinese than in English. Compared with input frequency, imageability independently accounts for a portion of the variance in age of acquisition (AoA) of verb learning in Chinese and English.

The purpose of the present study was to explore the contribution of phonological and general language skills to reading fluency of pointed and unpointed Hebrew scripts. Reading, language and memory tasks were performed by 48 fifth-grade monolingual native Hebrew speakers. Results showed that the most marked predictor for both pointed and unpointed reading texts was the morphological measure, whereas the phonological awareness measure contributed to neither of them. The semantic and syntactic measures contributed only to unpointed text reading fluency. The discussion highlights how readers in script, such as unpointed Hebrew, rely on general language skills in order to achieve fluent reading.

The aim of the study was to investigate the syllable activation hypothesis in French beginning readers. Second graders performed a lexical decision task in which bisyllabic words were presented in two colours that either matched the syllable boundaries or not. The data showed that the children were sensitive to syllable match and to syllable complexity. In addition, good readers were slowed down while poor readers were speeded up by syllable match. These findings suggest that syllables are functional units of lexical access in children and that syllable activation is influenced by reading level.

We assessed the effect of specificity of speaker information about an object on three-year-olds' word mappings. When children heard a novel label followed by specific information about an object at exposure, children subsequently mapped the label to that object at test. When children heard only specific information about an object at exposure, they inferred that the label applied to a different object at test. Finally, non-specific information did not assist children in mapping a word to an object. Thus, children use speaker information as a word-mapping cue but this information is interpreted differently depending on how the discourse is initiated.

Studies of English and German find that children tend to acquire word-final consonant clusters before word-initial consonant clusters. This order of acquisition is generally attributed to articulatory, frequency and/or morphological factors. This contrasts with recent experimental findings from French, where two-year-olds were better at producing word-initial than word-final clusters (Demuth & Kehoe, 2006). The purpose of the present study was to examine French-speaking children's longitudinal acquisition of clusters to determine if these results replicate developmentally. Analysis of spontaneous speech productions from two French-speaking children between one and three years confirmed the earlier acquisition of initial clusters, even when sonority factors were controlled. The findings suggest that French-speaking children acquire complexity at the beginnings of words before complexity appears word-finally. The role of frequency, morphological, structural and input factors is discussed.

Is parental report of comprehension valid for individual words? If so, how well must an infant know a word before their parents will report it as ‘understood’? We report an experiment in which parental report predicts infant performance in a referent identification task at 1 ; 6. Unlike in previous research of this kind (i.e. Houston-Price, Mather & Sakkalou, 2007), infants saw items only once, and image pairs were taxonomic sisters. The match between parental report and infant behaviour provides evidence of the item-level accuracy of both measures of lexical comprehension, and informs our understanding of how British parents interpret standardized Communicative Development Inventories (CDIs).

Nativist and constructivist accounts differ in their characterization of children's knowledge of grammatical categories. In this paper we present research on the process of acquisition of a particular grammatical system, gender agreement in the Spanish noun phrase, in children under three years of age. The design of the longitudinal study employed presents some variations in relation to classical studies. The aim was to obtain a large corpus of NP data which would allow different types of analysis of the children's productions to be carried out. Intra-individual variability in early NP types was analyzed and measured, and an elicitation task for adjectives was used. Results show that the acquisition of NP and gender agreement is a complex process which advances as the children gradually integrate different pieces of evidence: phonological, distributional and functional. The reduction of variability as the grammatical process advances is a key feature for its explanation.

Parent report instruments adapted from the MacArthur-Bates Communicative Development Inventories (CDI) examined vocabulary development in children aged 0 ; 8 to 2 ; 6 for two Chinese languages, Mandarin (n=1694) and Cantonese (n=1625). Parental reports suggested higher overall scores for Mandarin- than for Cantonese-speaking children from approximately 1 ; 4 onward. Factors relevant to the difference were only-child status, monolingual households and caregiver education. In addition to the comparison of vocabulary scores overall, the development of noun classifiers, grammatical function words common to the two languages, was assessed both in terms of the age and the vocabulary size at which these terms are acquired. Whereas age-based developmental trajectories again showed an advantage for Beijing children, Hong Kong children used classifiers when they had smaller vocabularies, reflecting the higher frequencies and greater precision of classifier use in adult Cantonese. The data speak to the importance of using not just age, but also vocabulary size, as a metric by which the acquisition of particular linguistic elements can be examined across languages.