This study describes how young Spanish-speaking children become gradually more adept at encoding temporality using grammar and discourse skills in intra-conversational narratives. The research involved parallel case studies of two Spanish-speaking children followed longitudinally from ages two to three. Type/token frequencies of verb tense, temporal/aspectual markers and narrative components were analyzed to explore interrelationships among grammatical and discourse skills. Children progressed from scattered unsystematic means of encoding temporality to mastering a basic linguistic system that included devices to mark location of events, temporal relations and aspectual meanings. The consolidation of perfective past tense to express narrative events marked a crucial developmental point which preceded an explosion of additional verb tenses and temporal markers. The value of spontaneous language data, and the need to study grammar and discourse simultaneously to construct a comprehensive developmental picture are highlighted. Results are discussed in relation to theoretical proposals on the development of temporality.

Two studies examined the role of phonological cues in the lexical categorization of new words when children could also rely on learning by exclusion and whether the role of phonology depends on extensive experience with a language. Phonological cues were assessed via phonological typicality – an aggregate measure of the relationship between the phonology of a word and the phonology of words in the same lexical class. Experiment 1 showed that when monolingual English-speaking seven-year-olds could rely on learning by exclusion, phonological typicality only affected their initial inferences about the words. Consistent with recent computational analyses, phonological cues had stronger impact on the processing of verb-like than noun-like items. Experiment 2 revealed an impact of French on the performance of seven-year-olds in French immersion when tested in a French language environment. Thus, phonological knowledge may affect lexical categorization even in the absence of extensive experience.

Language in autism has been the subject of intense interest, because communication deficits are central to the disorder, and because autism serves as an arena for testing theories of language acquisition. High-functioning older children with autism are often considered to have intact grammatical abilities, despite pragmatic impairments. Given the heterogeneity in language skills at younger ages, this assumption merits further investigation. Participants with autism (n=21, aged nine to seventeen years), matched on chronological age, receptive vocabulary and IQ, to 22 typically developing individuals, completed a grammaticality judgment task. Participants with autism were significantly less sensitive than controls, specifically for third person singular and present progressive marking. Performance interacted with sentence length, with lower sensitivity to errors occurring at the end of the longest stimulus sentences. Performance sensitivity was associated with onset of single word and phrase speech, and with severity of autistic symptomatology. Implications of findings are discussed.

This paper discusses different approaches to language acquisition in relation to children's acquisition of word order in wh-questions in English and Norwegian. While generative models assert that children set major word order parameters and thus acquire a rule of subject–auxiliary inversion or generalized verb second (V2) at an early stage, some constructivist work argues that English-speaking children are simply reproducing frequent wh-word+auxiliary combinations in the input. The paper questions both approaches, re-evaluates some previous work, and provides some further data, concluding that the acquisition of wh-questions must be the result of a rule-based process. Based on variation in adult grammars, a cue-based model to language acquisition is presented, according to which children are sensitive to minor cues in the input, called micro-cues. V2 is not considered to be one major parameter, but several smaller-scale cues, which are responsible for children's lack of syntactic (over-)generalization in the acquisition process.

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.

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.

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.

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.

This paper reports on partial knowledge in two-year-old children's learning of the regular English plural. In Experiments 1 and 2, children were presented with one kind and its label and then were either presented with two of that same kind (A→AA) or the initial picture next to a very different thing (A→AB). The children in A→AA rarely produced the plural. The children in A→AB supplied the singular form of A but children in A→AA did not. Experiment 3 compared the performance of English-speaking and Japanese-speaking children in A→AA with common and novel nouns. The Japanese-speaking children (learning a language without a mandatory plural) supplied the singular form of A but the English-speaking children did not. The findings indicate young children learning English know there is a plural to be learned before they have fully worked out the rules of production or acquired the necessary singular–plural pairs for broad generalization.

Infants at 1 ; 2 demonstrate difficulty in accessing subtle phonetic information about newly learned word–object pairings (Stager & Werker, 1997). In this study, we examined whether or not infants can access subtle prosodic information such as lexical stress in a word learning task. We tested infants younger than 1 ; 2 to see if they could learn two new word–object associations that differ only in stress pattern (Sww versus wSw). Our results are the first to demonstrate that, even without contextual support, infants at 1 ; 0 succeed at this task, suggesting that the salient acoustic properties associated with lexical stress facilitate word–object associative learning.