Developing knowledge of the vehicle, animal, and fruit categories was traced in six children from 1; 0 to 1; 8. Data from mothers' language diaries and from bi-monthly sessions with the children were pooled to analyse the growth, content, and internal structure of the three categories over time. The children developed some grasp of most of the focal concepts in each category, but they made fewer differentiations than adults do. Overextension of a single concept term to encompass a cluster of related referents was common. The frequent discrepancies between comprehension and production of concept terms highlighted the importance of examining both modes. The data showed marked individual differences in style of category acquisition.

A methodological study was designed to investigate two aspects of children's language knowledge and children's uses of pictures and objects when demonstrating their language skills. Sixty-eight 4- and 5-year-olds were randomly assigned to one of six treatment groups, matched for SES, sex, and age. Subjects were individually tested with one of the six measures: language comprehension using object stimuli; comprehension with picture stimuli; comprehension where there were choices among object stimuli; language production using object stimuli; production with picture stimuli; or production with choices among the object stimuli. Main effects for stimulus medium and response mode were both significant, as well as the interaction. The discussion is oriented towards the developmental controversy around receptive and productive language skills and the impact of the representational medium upon performance in assessment tasks.

The late babbling productions of a French child are analysed and compared with a similar study of English-speaking children. English-speaking and French children are shown to share such universal phonetic preferences as cluster reduction, final devoicing, etc. However, there are also noticeable differences which may be ascribed to corresponding differences in the target language. Thus a selective, language-specific, phonetic acquisition has been taking place during the babbling stage. A comparison of the phonetic repertoires of French, English, Thai and the late babbling corpus confirmed the close similarity between the latter and French. This study reinforces the view that babbling is relevant to the study of linguistic performance.

The temporal organization of the late babbling of a French child during the pivotal period between babbling and the production of meaningful utterances is studied. Two points are analysed: the segmental timing in terms of syllabic durations and the durations of sequences according to their intonational contours. Articulation rate in late babbling is fairly rapid and stable and does not vary with length of sequences. However, at the end of the period studied, longer durations are found for bi- and tri-syllabic sequences. This lengthening can be seen to reflect changes in the child's target programming and the constraints on co-articulation that it implies. Additional changes occur also as a function of intonational contours.

Recent research on single-word language has focused on the acquisition of object words, considering relational words such as more, allgone, here, and up only peripherally. These words are considered in relation to the operative schemes of sensorimotor intelligence as suggested by Sinclair (1970). Relational words, like syntactic structure, appear to develop and exist apart from specific content. Study of such words helps clarify the relationship between sensorimotor understandings and the language of the pre-operational child. Data spanning the entire single-word period from five subjects provide an empirical base for analysing the meanings of these words in use. A model is then proposed for considering relational words as coding a set of interrelated meanings reflecting the cognitive organization of the late sensorimotor period.

Various kinds of children's lexical errors, mostly based on similarity in sound, are presented and classified. At the earliest stage some children are found to pursue a HOMONYM STRATEGY, actively seeking to combine adult word-patterns to limit their output repertoire. The associations between words underlying these productive homonyms, together with perception-based errors, blends, and other word-substitutions, are compared with malapropisms from a slightly older group of children as well as with data from adults. Analysis of these data makes it possible to chart developmental changes in the phonological links which form one substructure of the lexicon.

The paper examines the acquisition of selected aspects of the inflectional system of Modern Hebrew, a language rich in bound morphology. By age three, children acquire the major inflectionally marked categories of the system, in the sense that they make semantically relevant distinctions of tense, person, number, and gender. Certain morphologically complex forms are simplified by neutralization or reformulation or by analytic paraphrases of bound constructions. Various anomalous forms are handled by regularization of lexical exceptions or by conflating forms belonging to different lexical patterns, while forms which are opaque due to neutralization of historically distinct root consonants or to inaccessibility of rules governing their alternations are processed by reference to certain ‘paradigms’ taken as basic.

The relationship between language development and the development of non-verbal representation was studied longitudinally in six children. Language development is evaluated interactionally by considering not only the form and usage of a child's sounds but also the way a familiar person allows those sounds to function as instances of words belonging to the frequently revised language proper to the child–adult pair. Non-verbal representation, studied in a symbolic play situation, presents different behavioural levels, showing close synchrony with a large increase observed in language development. The results are taken as suggestive of an inter-relational hypothesis between language and non-verbal representation, and an interpretation in terms of reciprocal interaction is proposed.

TURNABOUTS, which both respond to and require a response from the other (either verbal or nonverbal), were produced more than twice as often by mothers as by their children at 2; 2 and 2; 6, in videotaped dialogues during semi-structured play. The 27 mothers showed stable individual differences in this aspect of their turn-taking, across situations and across time. Children tended to take a reciprocal role rather than an imitative one within the immediate situation: if a mother produced many mands, her child produced few. At 2; 10 the children were tested for language comprehension, puzzle-solving and conversational engagement with an investigator. Mothers' mands at the earlier ages appeared to have a negative effect upon these measures, even when social class differences were controlled; but causal interpretations were complicated by the fact that language production measures also predicted the 2; 10 cognitive measures.

Investigators have targeted the onset of reference in children at varying points on the developmental continuum. Their viewpoints seem to be related to issues of the contextual flexibility, content and composition of the lexicon in comprehension and production. This study considered all of the variables in the early vocabularies of 32 children with a mean age of 1; 1·7. An intensive maternal interview was used to obtain data on the words comprehended and produced by the children and the contexts which supported their interpretation and use. The findings pointed to a relative independence between the domains of comprehension and production. Vocabulary size was related to all contextually flexible items in production while only related to the contextually flexible predicates in comprehension. Further, there was evidence for an early version of the referential style that has been reported at later stages of development.

An allative bias has been noted in children's comprehension of deictic verbs and directional prepositions. This study investigates the allative bias and its susceptibility to contextual modification. Three-year-olds were asked to act according to requests to move one object to or from another, and to identify where an object had come from or gone to. A reliable bias was found whereby ‘to’ was easier than ‘from’. Attempts to make the utterance more naturally related to the task, by using movement and fronted objects, modulated the bias to a small extent, but did not abolish it. An analysis of directional expressions in terms of the components SOURCE, PATH and GOAL is presented in relation to the task-demands.

The structure of contingent query sequences within adult–child discourse was examined. The children, aged 1; 11–3; 0 in language stages I–III, demonstrated basic knowledge of the contingent query. Implications for conceptualizations of the young child's communicative competence and for theoretical formulations of the query sequence itself are discussed.

Child partners were compared on their relative tendency to use the interrogative form in spontaneous dyadic verbal interactions. A given child's tendency to use the interrogative form more frequently than the other member of the dyad remained constant across partners. This relative stability in formulating utterances in interrogative form cannot be attributed to the child's producing more talk in general than the partner. The observed effect is explained as a type of conversational synchrony in which participants achieve a complementary balance rather than congruence. It was concluded that the interrogative form is a linguistic means for child peers to establish cooperation as well as controlling kinds of relationships during an ongoing interaction.

This study is an attempt to trace the acquisition of consonant clusters by Telugu children. Phonemic inventories are given for each of the children for a clear picture of their acquisitional stage. It was found that reduction, substitution and assimilation played major roles in cluster acquisition. Co-occurrence restrictions and hierarchical application of the three phonological processes were noted. Results of this study are compared with similar works on Indian languages and English, and differences are pointed out.

Mother and child speech in two half-hour free play conversations of six pairs were analysed for 15 semantic roles such as AGENT and ACTION, and five additional syntactic categories such as negation. Children were taped at the beginning of word combinations (1; 7–2; 0) and again 3 to 6 months later. Mothers and children were similar to one another in the relative frequency with which they used the different semantic and syntactic categories. However, the mothers' use was stable, including a larger number of categories than the children and showing few shifts in relative frequency. Insofar as changes took place over time, it was the children who changed to become more like their mothers, both in the semantic roles present and in their relative frequency of use. These findings are interpreted as evidence against a Fine-Tuning Hypothesis to explain the content of mothers' speech to children. The role of discourse topic restrictions in limiting the distribution of semantic roles is discussed.

The study considers implications of our findings regarding pre-school acquisition of Hebrew inflectional morphology (Berman 1981). Children resolve ‘opacities’ by reference to various types of ‘paradigms’. These are related to the distinction between transient and more widespread deviations from prescriptive norms, in an attempt to account for interactions between child language and language change. While pre-school acquisition is crucially affected by peer input, the grammar is subsequently reshaped by orthography and by formal study, yielding a complex interaction between concrete vs. abstract bases of Hebrew linguistic competence. Further research is needed to examine when and how the peculiarly Semitic constructs of consonantal root plus morphological pattern are acquired.

Three experiments investigated the ability of children aged 2; 2–4; 10 to use identifying expressions to introduce new referents and the definite article to refer to already introduced referents. The results suggest that young children initially master the nominative use of a, but that from the age of 3 they have mastered the non-egocentric use of the definite article. On first mention their referring expressions are predominantly indefinite, and on second mention definite. The results are discussed in relation to previous studies, and the questions of suitable adult controls and ‘appropriateness’ of article usage are also considered.

The pronoun system provides a fruitful area for investigating the conditions under which children make linguistic generalizations. Pronouns are defined by a complex of semantic, syntactic, and morphological distinctions whose interaction is only partially consistent. In the course of acquiring them, children often make systematic errors which reflect novel generalizations from the adult input. A distributional analysis was applied to the errors made by 48 children in marking distinctions of person, possession, and case in their spontaneous use of pronouns. The analysis indicated that children do not make maximal generalizations which extend a particular feature to all related contexts. Rather, they acquire specific complexes of features, and are quite conservative in extrapolating from one feature complex to another.

Based on Clark & Lucy's (1975) study of adult comprehension of different types of indirect requests, this study addresses the questions: ‘How well are children aged 4 to 7 able to understand these same indirect requests?’ and ‘How does the relation between request type and ease of comprehension compare from children to adults?’ Results showed: (1) these children are able to comprehend a wide variety of indirect requests; (2) there is a general developmental pattern of acquisition; (3) interrogative forms are more difficult than declarative forms; (4) conveyed negative requests are more difficult than corresponding conveyed positive requests; (5) children are heavily influenced by the surface polarity of the conveyed request; and (6) the relationship between request type and ease of comprehension is strikingly similar for both children and adults.