The present study tested the hypothesis that children as young as two use what adults tell them about meaning relations when they make inferences about new words. 18 two-year-olds (mean age 2;2) and 18 three-year-olds (mean age 3;2) learned two new terms (a) with instructions either (i) to treat one term as a superordinate to the other, or (ii) to replace one term with another; and (b) with no instruction given about how two new words might be related. Children were attentive to both kinds of instructions or pragmatic directions, and made use of them in their word-learning. When they received no instruction relating the two new words, they resorted to a range of coping strategies to assign and relate meanings to each other. These findings support the view that children's learning of new word meanings is guided by the pragmatic directions adults offer.

Generic noun phrases (e.g. Tigers are fierce) are of interest for their semantic properties: they capture ‘essential’ properties, are timeless, and are context-free. The present study examines use of generic noun phrases by preschool children and their mothers. Mother–child pairs were videotaped while looking through a book of animal pictures. Each page depicted either a single instance of a particular category (e.g. one crab) or multiple instances of a particular category (e.g. many crabs). The results indicated a striking difference in how generics vs. non-generics were distributed, both in the speech of mothers and in the speech of preschool children. Whereas the form of non-generic noun phrases was closely linked to the structure of the page (i.e. singular noun phrases were used more often when a single instance was presented; plural noun phrases were used more often when multiple instances were presented), the form of generic noun phrases was independent of the information depicted (e.g. plural noun phrases were as frequent when only one instance was presented as when multiple instances were presented). We interpret the data as providing evidence that generic noun phrases differ in their semantics and conceptual organization from non-generic noun phrases, both in the input to young children and in children's own speech. Thus, this simple linguistic device may provide input to, and a reflection of, children's early developing notion of ‘kinds’.

This study focuses on the acquisition of subject–verb agreement in Brazilian Portuguese. A quantitative analysis of the data produced by a Brazilian child between the ages of 3;02.07 and 3;04.08 is presented. The overall error rate is low. However, a further and more detailed analysis reveals important contrasts both in the frequency of production of different verb inflections (as regards the person/number variables within the verb morphological system) and in the rate of subject–verb agreement errors associated with them. Our findings not only suggest that subject–verb agreement may be acquired piecemeal, but also that the learning of particular verb inflections may itself be a gradual process. Alternatives to the idea of rule-governed production – such as the child's reproducing frozen subject–verb strings previously produced by adults and blending different frozen strings into novel combinations – are discussed as processes which can shed some light on the pattern of both erroneous and correct production shown by this child.

Several theoretical and descriptive challenges are presented by children's phonological substitution errors which interact to yield the effect of a chain shift. Drawing on an archival study of the sound systems of five children (ages 3;5 to 4;0) with normal development and 47 children (ages 3;4 to 6;8) with phonological delay, one such chain shift, namely the replacement of target /Θ/ by [f] and the replacement of /s/ by [Θ/, was identified in the speech of six children from the two subgroups. Different derivational and constraint-based accounts of the chain shift were formulated and evaluated against the facts of change and the children's presumed perceptual abilities. An adequate account in either framework was found to require the postulation of underspecified and, in some instances, nonadult-like underlying representations. Such representations were able to reconcile within a single-lexicon model the presumed production/perception dilemma commonly associated with acquisition. Continuity was also preserved by limiting underlying change to just those lexical items which exhibited a change phonetically.

This study investigated the extent to which the nature of verb input accounts for the order in which children acquire verbs. We assessed the nature of verb input using a combined sample of the speech of 57 mothers addressing their Stage I children. We assessed the order of verb acquisition using as our database a combined sample of those children's speech 10 weeks later and using as our measure of order of acquisition the frequency of verb occurrence. The first set of analyses established the validity of this measure of acquisition order by comparing it with order of acquisition data obtained from checklist and diary data. The second set of analyses revealed that three properties of the input were significant predictors of the order of acquisition of the 25 verbs that were the focus of this study. The predictive properties of input were the total frequency, final position frequency, and diversity of syntactic environments in which the verbs appeared. These findings suggest that the way verbs appear in input influences their ease of acquisition. More specifically, the effect of syntactic diversity in input provides support for the syntactic bootstrapping account of how children use structural information to learn the meaning of new verbs.

An empirical puzzle regarding toddlers' fast mapping motivated the current investigation. Whereas children between 1;10 and 2;1 have shown only a modest rate of mapping novel nouns onto unfamiliar rather than familiar objects, a very high rate has been observed in those between 1;4 and 1;8 (Mervis & Bertrand, 1994). Study 1 examined whether young two-year-olds (N=40, mean age=2;1) might map at a higher rate when tested with procedures unique to Mervis & Bertrand's assessment – strong corrective feedback rather than mild positive non-contingent feedback; large sets of test objects rather than pairs; presentation of easier tests first. Only the first variable affected performance in a manner that could solve the puzzle. Unfamiliar kinds were selected at a much higher rate under corrective (0·86) than non-contingent (0·57) feedback. Although nearly every child in the non-contingent group chose correctly on the first trial, many failed to do so thereafter. In Study 2, rather than presenting a test word to the children (N=16, mean age=2;2), the experimenter merely asked for ‘the one I want’. Unfamiliar kinds were selected much less often than in Study 1, suggesting that at least one lexical principle proposed in the literature underlies the noun mapping preference. Changes over trials in the two studies indicated that the noun mapping preference is quite prevalent, but unless initial choices are strongly reinforced, an increase in the salience of familiar kinds after the first trial lures some children into error. Consistent with this analysis, toddlers in Study 3 (N=24, mean age=2;1) who received non-contingent strong acceptance for their noun mapping decisions, selected unfamiliar kinds more often than those who had received non-contingent mild acceptance in Study 1.

The aim of this study was to determine if mothers display identifiably different communicative styles in their interaction with their normally developing two- to five-year-old children. In order to investigate this issue an extensive coding system was developed, which assessed the structural organization and the communicative function of the speech of 71 mothers as they interacted with their children. By means of factor analysis three maternal communicative styles were distinguished: non-intervening, explaining and directing. In the non-intervening style there is no direct pressure from the mother on the child to respond verbally. The explaining mother is primarily concerned with providing information to her child in a way that gives the child little opportunity to take the speaking turn. The directing mother is mainly engaged in directing the child's behaviour by means of verbal control. The internal consistency of the three communicative styles appeared to be both satisfactory and related to relevant child and mother features.

Maternal infant-directed speech in Mandarin Chinese and Turkish (two mother–child dyads each; ages of children between 0;11 and 1;8) was examined to see if cues exist in input that might assist infants' assignment of words to lexical and functional item categories. Distributional, phonological, and acoustic measures were analysed. In each language, lexical and functional items (i.e. syllabic morphemes) differed significantly on numerous measures. Despite differences in mean values between categories, distributions of values typically displayed substantial overlap. However, simulations with self-organizing neural networks supported the conclusion that although individual dimensions had low cue validity, in each language multidimensional constellations of presyntactic cues are sufficient to guide assignment of words to rudimentary grammatical categories.

In her inceptive study of promising, Astington (1988) found that five-year-olds failed to distinguish promises from predictions when judging story characters' utterances. Instead, their responses were based on whether the promised event had actually occurred. There is reason to believe, however, that the children's poor performance was an artefact of Astington's procedures. We tested this possibility with 32 children (mean age 5;8: range 5;7–6;2) by including several variations of Astington's procedures, but found no effects on the pattern of results. This suggests that Astington's findings are an accurate reflection of the developmental course of knowledge about promising.