Three children were observed interacting with their mothers at three different times: before the onset of single words, when vocabulary consisted of 10 words, and when vocabulary consisted of 50 words. Relations between communicative functions and acoustic analyses of prosodie variables (i.e. rise vs. nonrise of terminal contours) were studied. Considerable variability was found among the children in the number of rises produced overall and those produced for any function. Each child's use of rise was fairly constant over time and rises were produced RELATIVELY more frequently than nonrises with functions requiring a response from the listener. Factors affecting similarities and differences are discussed.

In Harris, Barrett, Jones & Brookes (1988), we reported the results of a detailed analysis of the initial uses of the first 10 words which were produced by four children. The present paper reports the results of an analysis of the subsequent uses of these 40 words. This analysis reveals that seven qualitatively different patterns of change occurred between the children's initial and subsequent uses of these words; the particular patterns of change which occurred support Barrett's (1986) model of early lexical development. In addition, it was found that, although there was a strong relationship between maternal speech and the children's initial word uses, the relationship between maternal speech and the children's subsequent word uses was very much weaker. These findings indicate that the role of linguistic input in early lexical development may decline quite sharply once the child has established initial uses for words.

Maternal directiveness, assessed by the mother's use of prescriptives, is correlated with slow vocabulary development. As prescriptives are most often used to redirect a child's attention to a different object or activity, it is hypothesized that attentional regulation underlies this negative relationship. In the present study, twelve mothers were videotaped interacting with their children aged 1;1, and 100 maternal utterances were coded for pragmatic intent. Prescriptives were coded as either changing (LEADING) or FOLLOWING the child's focus of attention. Only the frequency of mothers' FOLLOW-prescriptives correlated significantly with a productive vocabulary measure taken at 1;10. This correlation was high and positive, indicating that, given joint focus, directing a 13-month-old's behaviour can have beneficial effects on subsequent vocabulary development.

The development of forms and functions of negation in parent–child interactions in the early stages of language acquisition is discussed with illustrative examples from field data relating to two Tamil-speaking children and their parents. An attempt is made to provide a scheme for analysing the negatives in children's speech, maintaining the three basic functions of Bloom (1970) unaltered. Subcategories of these functions are introduced, taking into consideration the interactional situations as they are perceived by the parents and children. Children, it is observed, acquire the forms and functions of negation in a clear developmental sequence. They acquire and use the free forms naanaa (veeṇḍaam) ‘No, I don't want’ first, followed by negatives involving bound forms. Certain forms like maaṭṭeen ‘I won't’, muḍiyaadi' I can't’ and even veeṇḍaam are used in isolation (as free forms) first. Only later are they used with verb infinitives. The development of functions of negation follows the sequence: rejection, non-existence, prohibition and denial. Thus the children of this study show preference for rejection over non-existence as observed by earlier scholars.

The purpose of this research was to evaluate the development of temporal location within a cross-linguistic experimental design. The research focused on the transition from a temporal system based on absolute temporal relations involving speech time and event time to a more complex system involving relative temporal relationships and reference time. A comprehension test was constructed with problems which were diagnostic of two salient distinctions within each of three temporal systems. The procedure was based on a two-choice sentence–picture matching task. The children who participated were from Poland, the USA and Finland, and there were 12 children at each of the following age levels: 2;6, 3;6, 4;6, 5;6, and 6;6. The Polish and American children solved problems requiring absolute temporal location at 2;6, and the older children eventually solved most of the problems requiring relative location. The Finnish children followed a different pattern taking longer to comprehend both types of problems. A second experiment confirmed the Finnish pattern of development. The results of the comprehension test were compared to observations of conversational and narrative discourse which were the product of two elicitation procedures. The research demonstrates the way in which conceptual development places a universal constraint on the developmental process and how the specific properties of individual languages also have an effect.

An experimental elicitation task with children between the ages of 1;8 and 11;3 shows that children learning Thai numeral classifiers begin with purely distributional information: specifically, (1) that classifiers must appear in the post-numeral position, and (2) that classifiers comprise a conventional, closed set of words. Semantic organizing features, such as salient features of the head noun's referent, appear later than these syntagmatic organizing features. Use of such semantic information is not an immature ‘first guess’ at grammatical categories, but rather, a necessary component of adult linguistic competence, because the categories are productive both for older children and for adults.

Children between the ages of three and seven occasionally make errors with locative verbs like pour and fill, such as * I filled water into the glass and * I poured the glass with water (Bowerman, 1982). To account for this pattern of errors, and for how they are eventually unlearned, we propose that children use a universal linking rule called OBJECT AFFECTEDNESS: the direct object corresponds to the argument that is specified as ‘affected’ in some particular way in the semantic representation of a verb. However, children must learn which verbs specify which of their arguments as being affected; specifically, whether it is the argument whose referent is undergoing a change of location, such as the content argument of pour, or the argument whose referent is undergoing a change of state, such as the container argument of fill. This predicts that syntactic errors should be associated with specific kinds of misinterpretations of verb meaning. Two experiments were performed on the ability of children and adults to understand and produce locative verbs. The results confirm that children tend to make syntactic errors with sentences containing fill and empty, encoding the content argument as direct object (e.g. fill the water). As predicted, children also misinterpreted the meanings of fill and empty as requiring not only that the container be brought into a full or empty state, but also that the content move in some specific manner (by pouring, or by dumping). Furthermore, children who misinterpreted the verbs' meanings were more likely to make syntactic errors with them. These findings support the hypothesis that verb meaning and syntax are linked in precise ways in the lexicons of language learners.

Young children's skilfulness in conversational interaction is of great importance in understanding pragmatic aspects of language development. The purpose of this investigation was to describe the portion of preschool verbal interaction which could not be considered successful dialogue. Ten dyads of four-year-olds were videotaped during free play. Segments of talk were identified as dialogue or non-dialogue. Non-dialogue was coded when one child did not appear to direct his/her utterances to the other or when an attempted topic failed to capture the interest of the other child. Thirteen types of non-dialogue were identified. Results revealed that all dyads exhibited non-dialogue, but differences were noted in regard to amount and type. Dyads labelled as less co-operative displayed greater amounts of self-directed talk (monologue).

Standard outcome measures used in a referential communication (route finding) task showed that 7-year-olds were inferior to 10-year-olds and adults in terms of adequacy of messages provided (as speakers) and selection of referent (as listeners). Because the task involved negotiation of route directions by telephone, a richer dialogue resulted than is usual in referential communication studies. This made possible an analysis of the strategies used and revealed differences untapped by the standard measures. The types of strategies used (COMPONENTS, NUMBERING, DIRECTIONAL, MINIMAL) varied as a function of age, with the adults using much directional information and the children very little. Much of the younger children's description was either minimal or used inadequately specified mature strategies. Adults frequently used dual strategies (e.g. directional + numbering). Older children showed little evidence of these individually but achieved them, in practice, through dialogue with their partners. Age differences in quantity of communication (number of turns) were found to be linked to strategy use. The advantages of the telephone as an experimental medium of communication are discussed.

The way seven- and nine-year-old French children and adults interpret ambiguous object descriptions was studied in four experiments. All four experiments followed the same basic procedure and consisted of two phases. During the training phase, plastic blocks varying in shape, colour and size were associated with fruit names. Some objects were always given just one label, the generic term, whereas others could be given either the generic or the specific label. For example, large circles were referred to as ‘pommes’ (‘apples’), and large BLUE circles as ‘reinettes’ (a kind of apple). Still others were given no name at all. During the test phase of the experiment, subjects were presented with referentially ambiguous messages and asked to point to a given object (Experiments 1, 2 and 3) or to draw an object (Experiment 4). The messages consisted of either a generic term preceded by an article (e.g. ‘(la pomme’ – ‘the apple’) or a verbal description based on a colour adjective (e.g. ‘le bleu’ – ‘the blue one’). When presented with the generic term, older children and adults persistently chose the object for which no specific term had been given during the training phase. When presented with an adjective description, they chose the referent for which no fruit name had been given during the training phase. Younger children's choices depended on whether the article preceding the description was definite or indefinite. These results are consistent with the Gricean approach to referential communication proposed by Jackson & Jacobs (1982) and with an extended version of the principle of contrast proposed by Clark (1987, 1988).

Garman (1974), reporting on twenty Tamil children aged three to five, postulated a linguistic strategy and two prelinguistic strategies to explain the results of a question-picture choice task involving sentences with embedded and subordinate clauses. In a reanalysis of his data, we identify four processing strategies and show that some of Garman's findings are better explained not as the outcome of prelinguistic strategies but as an artefact of the experimental design. In fact the data provide evidence of a grammatical sensitivity which is consonant with a sensitivity – demonstrated in recent language-acquisition studies – to the branching direction of the language being acquired.