College students judged the relative ages of pairs of vocalizations sampled either from a Chinese infant at 0; 6, 1; 0 and 1; 6 or from an American infant at the same ages. The judgments were 88% accurate, with the easiest judgments contrasting the 0; 6 and 1; 6 samples (96% accurate). With one exception, age contrasts for the Chinese infant were as easy to judge as those for the American infant. However, a second sample of college students was unable to judge the linguistic community of the vocalizer when age was held constant, whether the data were drawn from infant samples of 0; 6, 1; 0 or 1; 6 or from adults babbling to babies. These data led to speculations on the kinds of cues speakers of different languages use to discriminate infant vocalizations, and whether these cues are age-specific or language-specific. The data presently suggest the former, but the present study has methodological limitations, and generalizations are limited to one specific language contrast, English and Chinese.

The concern of this case study is to show how the parental terms for ‘mummy’ and ‘daddy’ in Latvian are acquired, paying particular attention to the changing relationship between the input and output forms during the acquisition process. We may note here three questions which we shall attempt to answer. (1) Are parental terms the earliest words used spontaneously by the young child? (2) Does their ‘easier’ word structure allow the child to acquire the adult forms for these words earlier than is the case for the rest of the vocabulary? (3) Do the function and meaning of these parental terms correspond to those of the adults', and if not, what is the difference? And how stable are the meanings of these words during the first years of life?

This study investigates the development of past tense expressions in the speech of children from 1; 6 to 2; 6. It is shown that this development depends crucially on the child's cognitive construction of the time dimension, as described by Piaget (1954, 1971). In this process two different cognitive routes are followed, depending on the type of event the child has to encode. Past events resulting in the end state of some object are gradually grasped and encoded by means of a practical process–effect coordination. Past states and activities, on the contrary, i.e. past events that do not result in an end state, are referred to through a more primitive distinction between a pretend vs. a real world. This difference is formally reflected in the differential past-tense marking appearing on verbs which describe the two different types of event.

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.

Two tasks were used to test predictions of the Semantic Feature Hypothesis (SFH) about children's comprehension of the meaning of spatial adjectives. Our data support SFH predictions about the order of acquisition for dimensional features: more general features are acquired first. Predictions about polarity, however, were not supported: our data show that children do not acquire [+ pol] features prior to their [− pol] counterparts. Type of task made no difference in children's comprehension of [+ pol] terms but did affect comprehension of [− pol] terms. To account for this pattern of results, an acquisition hypothesis is offered which, contrary to the SFH, proposes that polar features are acquired prior to dimensionality and that semantic features may be added quite independently to [+ pol] and [− pol] terms.

Interpersonal functions of everyday caretaker speech usage are examined when addressed to toddlers, threes, and fours. Twelve teachers, 4 at each age level, were each observed for 24 3-minute intervals during free play, and their speech classified into 45 responsive and spontaneous functional categories based on our previously developed classification scheme for spontaneous child speech (Schachter et al. 1974). The results support hypotheses derived from Piagetian theory concerning early developments in ego-differentiation. Speech patterns with increments in speech to toddlers include explicating desires, providing substitutes for prohibitions, reporting on the child, and word teaching, called alter-ego speech. Patterns with increments for threes and/or fours include enhancing the child's ego, assisting him to fulfil desires himself, and encouraging persistence, called ego-supportive speech, as well as modulations (explanations, justifications, etc.) and admonitions with appeals to norms, called ego-socializing speech. Implications for language acquisition are discussed.

The speech of children aged 11, in socially contrasted groups, was analysed across a range of communicative tasks. On most ‘traditional’ measures, consistent group differences did not appear. There were significant differences on measures directly derived from the ‘planning principles’ said by Bernstein to underlie restricted and elaborated codes. Even on these, however, there was considerable task variation. There was no evidence of rigidity in the speech of the lower-working-class children, and no evidence of a persistent orientation to one code rather than the other.