A large body of research shows that vocabulary does not develop independently of grammar, representing a better predictor of the grammatical complexity of toddlers' utterances than age. This study examines for the first time the characteristics of vocabulary and grammar development in Slovenian-speaking infants and toddlers using the Slovenian adaptation of the MacArthur-Bates Communicative Development Inventories (CDI). The sample included 512 Slovenian-speaking infants and toddlers aged 0 ; 8 to 2 ; 6. The findings suggest that between age 0 ; 8 and 2 ; 6 the development of vocabulary is best described using a quadratic function. The results also show that nouns predominate in the vocabularies of infants and toddlers of various ages; as they age and with the increasing size of their vocabularies, the share of interjections decreases and the share of verbs and adjectives increases. The size of vocabulary was also found to be related to the grammatical structure of toddlers' utterances.

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’.

Blind children are considered to use personal reference terms late and with a great deal of reversal errors. However, in previous research, there has been a dearth of both quantitative and qualitative data on their use of pronouns. In the present paper data from a longitudinal study of five children (three totally blind, one partially sighted, and one sighted) is presented. The children had different ages at the begining of the study, ranging from 0;9 to 2;5, and were followed for a time span of over 12 months. Every spatial deictic term and personal reference term used by the children was analysed. Special attention was given to the analysis of the reversal errors. The data obtained clearly showed that the blind children began to use personal reference terms as early as the sighted children, and that the use of reversals was not a general characteristic of the language of the blind children, since only one of the four blind or partially sighted children produced a noticeable percentage of reversals. The analysis of the contexts in which reversal errors were produced showed that imitation does not fully explain them, and some proposals for a multiplex explanation of reversals are offered. Thus, the data do not give support to the idea that blind children in general show problems with pronouns, nor to those claims that link blind children with autistic children in this regard.

An unusual phonological pattern exhibited by a child aged 2;9 is described. The pattern involved the production of word-final strident continuants in words whose adult forms contain these features in initial, rather than final position (e.g. [ops] for soap). The data are interpreted as compatible with models of child phonology that permit direct mapping of features to final position.

Gestures and vocal elements interact from the early stages of language development, but the role of this interaction in the language learning process is not yet completely understood. The aim of this study is to explore gestural accompaniment's influence on the acoustic properties of vocalizations in the transition to first words. Eleven Spanish children aged 0;9 to 1;3 were observed longitudinally in a semi-structured play situation with an adult. Vocalizations were analyzed using several acoustic parameters based on those described by Oller et al. (2010). Results indicate that declarative vocalizations have fewer protosyllables than imperative ones, but only when they are produced with a gesture. Protosyllables duration and f(0) are more similar to those of mature speech when produced with pointing and declarative function than when produced with reaching gestures and imperative purposes. The proportion of canonical syllables produced increases with age, but only when combined with a gesture.

One strategy that children might use to sort words into grammatical categories such as noun and verb is distributional bootstrapping, in which local co-occurrence information is used to distinguish between categories. Words that can be used in more than one grammatical category could be problematic for this approach. Using naturalistic corpus data, this study asks whether noun and verb uses of ambiguous words might differ prosodically as a function of their grammatical category in child-directed speech. The results show that noun and verb uses of ambiguous words in sentence-medial positions do differ from one another in terms of duration, vowel duration, pitch change, and vowel quality measures. However, sentence-final tokens are not different as a function of the category in which they were used. The availability of prosodic cues to category in natural child-directed speech could allow learners using a distributional bootstrapping approach to avoid conflating grammatical categories.

Language processing plays a crucial role in language development, providing the ability to assign structural representations to input strings (e.g., Fodor, 1998). In this paper we aim at contributing to the study of children's processing routines, examining the operations underlying the auditory processing of relative clauses in children compared to adults. English-speaking children (6;0–8;11) and adults participated in the study, which employed a self-paced listening task with a final comprehension question. The aim was to determine (i) the role of number agreement in object relative clauses in which the subject and object NPs differ in terms of number properties, and (ii) the role of verb morphology (active vs. passive) in subject relative clauses. Even though children's off-line accuracy was not always comparable to that of adults, analyses of reaction times results support the view that children have the same structural processing reflexes observed in adults.

Samples of spontaneous speech from seven two-year-olds were scanned for utterances containing the verbs go and come. Their distribution was extensive, and included many non-motional uses. No clear case of the wrong use of either verb was found and the children seemed to have a basis for discrimination. As verbs of motion, they were used in the context of describing the contour of movement rather than as means of relating end-points of a journey. This relation between systems of movement and location was taken to be crucial in explaining the child's long-standing difficulty in discriminating the verbs in experimental tasks.

Neighbourhood Density (ND) and Phonotactic Probability (PP) influence word learning in children. This influence appears to change over development but the separate developmental trajectories of influence of PP and ND on word learning have not previously been mapped. This study examined the cross-sectional developmental trajectories of influence of PP and ND on fast-mapping in thirty-eight English-speaking children aged 3 ; 01–5 ; 02, in a task varying PP and ND orthogonally. PP and ND exerted separable influences on fast-mapping. Overall, low ND supported better fast-mapping. The influence of PP changed across the developmental trajectory, ‘switching’ from a high to a low PP advantage. A potential explanation for this ‘switch’ is advanced, suggesting that it represents functional reorganization in the developing lexicon, which emerges from changes in the developing lexicon, as phonological knowledge is abstracted from lexical knowledge, over development.

The current study examined monolingual English-speaking toddlers' (N=50) ability to learn word–referent links from native speakers of Dutch versus English, and second, whether children generalized or sequestered their extensions when terms were tested by a subsequent speaker of English. Overall, children performed better in the English than in the Dutch condition; however, children with high native vocabularies successfully selected the target object for terms trained in fluent Dutch. Furthermore, children with higher vocabularies did not indicate their comprehension of Dutch terms when subsequently tested by an English speaker whereas children with low vocabulary scores responded at chance levels to both the original Dutch speaker and the second English speaker. These findings demonstrate that monolingual toddlers with proficiency in their native language are capable of learning words outside of their conventional system and may be sensitive to the boundaries that exist between language systems.

Ten objects were used to assess comprehension, production, and imitation of comparative and superlative suffixes in 100 children ranging in age from 2; 6 to 4; 6. The results indicated that comprehension of both suffix forms was similar at each of five age levels studied; although incrementally better comprehension scores occurred with succeeding ages. Virtually all subjects were successful in imitating forms missed during the comprehension task. Analysis revealed that the -er suffix was produced more often than the -est suffix, at the youngest age (2; 6): at succeeding age levels this difference was reversed. Big was the primary lexical unit selected by the subjects for positive and negative polar forms connoting size; little was the second most frequently used adjective form.

Most studies on CV co-occurrence patterns in early phonetic development have been based on Indo-European languages. Data from infants learning Mandarin, which has a substantially different phonological system from Indo-European languages, can confirm or refute the findings of previous studies, thus shedding further light on the theoretical bases of CV association. Spontaneous vocalizations were recorded in 45-minute sessions for each of 24 Mandarin-learning infants aged 0;7 to 1;6. In addition, the speech production of 24 caregivers was audio-recorded during their natural daily interactions with the infants at home. Both infants' vocalizations and adults' speech were transcribed and analysed for consonant–vowel co-occurrence patterns. These patterns were similar to those in other language groups, but language-specific patterns were evident by 1;0. Combinations of alveolars+front vowels and velars+back vowels confirm Davis & MacNeilage's (1990, 1995) frame-then-content theory and Clements's (1991) model of unified features for consonants and vowels. However, our finding of a language-specific pattern (labials+back vowels) suggests the need to reexamine the ‘pure frame’ of Davis & MacNeilage and Clements's grouping of labials and rounded vowels.

Pizzuto & Caselli (1992) claim that data from the morphosyntactic development of Italian-speaking children are inconsistent with nativist, parameter-setting models of language development. In the present Note it is argued that much of the data which Pizzuto & Caselli adduce is irrelevant to the specific hypotheses they are evaluating and that those data which are relevant fully support parameter-setting and linguistictheoretic models, contrary to their claims.

This paper explores the effects of certain aspects of verb input on verb acquisition. It has been observed that the timing of a verb model affects children's learning of the verb (Tomasello & Kruger, 1992). It has also been observed that the focus of the event to which the verb refers affects the argument structure children assign to the verb (Pinker, 1989). This experiment investigated the interaction between the timing of verb models and the focus of the events to which they refer. Thirty children aged from 2;3 to 3;6 heard two novel verbs, one movement focused and the other result focused. Half heard the verbs before the event (impending condition) and half after it (completed condition). An interaction of verb timing and verb focus was found. The movement verb was learned better in the impending condition and the result verb in the completed condition. The contribution of this finding to our understanding of the processes involved in verb acquisition is considered.

This study compared naturalistic samples of three features of language in 30 two-year-olds – total utterances, word roots, and MLU – in the home in three contrasting situations: the child observed playing by her/himself with mother near by, the child and mother observed in direct play interaction, and the child and mother unobserved at a time the mother judged would provide a sample of the child's ‘optimal’ language. Children produced more utterances and word roots and expressed themselves in longer MLU when in interaction than when playing ‘alone’, but children's utterances, word roots, and MLU were greatest in the ‘optimal’ language production situation. Girls used more word roots and spoke in longer MLU (especially in the ‘optimal’ language situation) than boys. Despite mean level differences, children maintained their rank orders across the three situations in use of word roots and in MLU. These findings have implications for understanding children's language and the representativeness of sampling child language.

Several competing proposals for the (under)specification of phonological representations are evaluated against the facts of phonemic acquisition. Longitudinal evidence relating to the emergence of a voice contrast in the well-documented study of Amahl (from age 2;2 to 3;11) is reconsidered. Neither contrastive specification nor context-free radical underspecification is capable of accounting for the facts. The problem is in the characterization of the change in the status of a feature from being noncontrastive and conditioned by context at one stage to being contrastive with phonetic effects that diffuse gradually through the lexicon. Both frameworks must treat as accidental the persistence of the early substitution pattern and require the postulation of wholesale changes in underlying representations, where these changes do not accord well with the observed phonetic changes or with the facts available to the learner. Context-sensitive radical underspecification provides a plausible account of each stage and the transition between stages with minimal grammar change.

Young children's productions of novel words serving as names of objects and actions were compared. Although the object and action names were matched according to consonant and syllable structure, accurate production of newly emerging consonants was greater for the object words for each of the measures used: spontaneous production and unsolicited imitation during the word exposure sessions, and responses to production probes administered during and following the exposure sessions. These findings are attributed to the fact that action words have greater semantic complexity than object words, and that the increased processing requirements involved in referring to actions reduce the capacity to use newly developing sounds in these words.

The study examines strategies multilingual children use to interpret grammatical relations, focusing on their two primary languages, Lajamanu Warlpiri and Light Warlpiri. Both languages use mixed systems for indicating grammatical relations. In both languages ergative–absolutive case-marking indicates core arguments, but to different extents in each language. In Lajamanu Warlpiri, pronominal clitics in a nominative–accusative pattern also indicate core arguments, and in Light Warlpiri word order in a nominative–accusative pattern partially does so. The study asks which sentence interpretation strategies children rely on most, when they learn to rely on them and whether cross-linguistic influences are seen. Children aged 5 ; 0, 7 ; 0 and 9 ; 0 and adults saw paired, animated events simultaneously on video and heard a transitive sentence spoken. The participants pointed to the event depicted by the sentence heard. Adults used a case-marking strategy consistently in both languages. Children initially used both case-marking and word order strategies, but used case-marking more often as age increased.

Hearing words in sentences facilitates word recognition in monolingual children. Many children grow up receiving input in multiple languages – including exposure to sentences that ‘mix’ the languages. We explored Spanish–English bilingual toddlers’ (n = 24) ability to identify familiar words in three conditions: (i) single word (ball!); (ii) same-language sentence (Where's the ball?); or (iii) mixed-language sentence (Dónde está la ball?). Children successfully identified words across conditions; however, the advantage linked to hearing words in sentences was present only in the same-language condition. This work hence suggests that language mixing plays an important role on bilingual children's ability to recognize spoken words.