These are the principal questions of this study: are the early fonctions of negation, such as REJECTION, and the later emerging DENIAL no developmentally related? And when do children start to deny? So far, evidence for the questions at hand has been almost exclusively observational. We decided on a simple elicitation procedure instead, asking 48 children (ages between 1;1 and 2;7) easy yes/no-questions. The most likely age range for the appearance of denial no was 1;8–2;1. Its error-free acquisition supports the continuity theory of negation development, which holds that essentials of denial no carry over from the earlier fonctions of no. Finally an attempt is made to account for the beginnings of denial in terms of semantics and the representational theory of child cognition.

The validity of MLU and a measure of syntactic complexity were tested against LARSP on spontaneous speech samples from 87 children, ranging in age from 1;6 to 4;9. Change in some LARSP clausal measures was found across MLU stages up to MLU 4.5. For the measure of syntactic complexity, no such ceiling was found for the clausal connectivity score in LARSP or for average clausal complexity in LARSP. Neither MLU nor the measure of syntactic complexity indexed LARSP phrasal complexity. It is concluded that MLU is a valid measure of clausal complexity up to 4·5 and that our measure of syntactic complexity is more valid at more advanced stages.

In different languages children have been found to use past verb forms to express the meaning of ‘unreality’ during social pretend play. In this study, the verb forms used by 14 four-year-old Italian children in their pretend play were investigated. Results show that different Italian past verb forms tend to co-occur with different play activities. The imperfect occurs mainly when children plan and negotiate their pretend activities and marks the transition from a real to a pretend frame of reference. The present perfect occurs mainly when children implement their plans and communicate within a pretend frame that has already been established. Results of this study are discussed in comparison with findings on the pretend language of children speaking other languages.

A recurring result from studies which relate the frequency of input variables to rate of language development, is the link between auxiliary verb growth and yes—no questions addressed to children. Explanations for this relationship usually concentrate on the advantages of hearing stressed and non-contracted auxiliary forms in sentence-initial position over hearing unstressed, contracted forms in medial position in declaratives. If such accounts are correct, then it can be predicted that yes—no questions which place forms of COPULA be in initial position will also increase the rate of growth of children's COPULA verb development. This prediction was tested using a sample of 33 children, carefully matched for stage of language development at 1;9 and 2;0 years; rate of copula verb growth was then measured over the succeeding nine months. Analyses include an examination of the contribution of sub-categories of yes—no question, tag questions, and utterances containing sentence-final copulas to the growth of contracted and full copulas. Results confirm that the frequency of inverted copulas in yes—no questions predicts children's copula development. Nevertheless, caution is urged before interpreting the relationship in terms of a direct causal model.

The study examines children's command of transitivity permutations in Hebrew, where a change in verb-argument syntax entails a change in verb-morphology. 30 children aged two, three and eight were required to produce existing and novel Hebrew verbs differing in transitivity. Younger children showed a good grasp of the syntax and semantics, but not the morphological marking of transitivity, three-year-olds did much better, and eight-year-olds produced mainly adultlike responses. Results were higher on existing verbs than on novel forms. Direction of change had little effect with existing verbs, but with novel verbs success was much higher in changing intransitive to transitive forms than the converse. Some alternations proved easier than others, e.g. intransitive activity verbs in the basic pa'al verb-pattern yielded more causative hif'il forms than intransitive inchoative verbs in the nif'al pattern. Findings throw light on the development of derivational morphology, item-based versus class-based learning, and the impact of lexical productivity and language-particular properties on acquisition.

Mothers have been found to respond differently to grammatical and ungrammatical utterances in young children's language. However, parents indicate that they are conscious only of responding to communicative aspects of their children's speech, not grammar. Further, researchers have looked to the understandability of utterances to explain the effects of grammaticality on maternal responses. The present study addressed the question of whether it is actually grammatical form that mothers respond to, or whether it is ambiguity in the communicative functions of children's utterances. Three mother-child dyads were videotaped in a free play setting when the children were 2;0 and 3;0. Children's spontaneous comprehensible utterances were rated for grammaticality and ambiguity of function, and mothers' responses to them were noted. Results indicated that mothers responded differentially to both the ambiguity and grammaticality of children's utterances, and that these two factors had some degree of independence in their effects on mothers' responses.

This study examined the development of children's comprehension of the use of intonation and belief verbs to mark the relative certainty with which a speaker makes a statement. Subjects were presented with a task in which they had to guess the location of an object hidden in one of two boxes over a series of trials. As clues to location, the children were presented with contrasting pairs of statements by two puppets. In the first experiment with 30 children at each of three, four, five and six years of age, statements in each pair differed either with respect to the belief term included – know, think or guess – or with respect to terminal pitch contour – rising or falling. Results showed that three-year-olds did not use any information reliably to determine the location of the object, four-year-olds treated falling pitch as a more reliable indicator of location than rising pitch, and older children responded on the basis of the belief terms but not on the basis of prosody. In Experiment 2, 40 children at each of three, four and five years heard statements which differed with respect to both belief verbs and prosody. In one condition falling intonation was paired with the more certain belief term in each pair, and rising intonation with the less certain pair. In a second condition, the pairings were reversed. Results showed that, while four-year-olds could tell the difference between know and think, they could not use intonation information to determine the location. Five-year-olds used both lexical and prosodic information, with prosodic eues modulating the effects of lexical. Taken together, these experiments show that prosodic and lexical cues start to be used by children to interpret relative speaker certainty at about the same time developmentally, but that lexical cues initially appear to dominate while prosodic ones modulate their effects. Finally, it is argued that children's understanding of prosody will be best revealed in contexts in which they are required to respond to the pragmatic function of verbal stimuli rather than to the lexical content.

The speech children spontaneously quote was examined in two studies. In Study 1, a corpus of personal narratives from 96 children aged 4;0 to 9;0 was analysed; Study 2 investigated reported speech in 25 younger children aged 1;2 to 5;2 interacting with their parents. In both studies, the frequency of reported speech increased with age. Direct quotation was more common than indirect or summarized quotation at all ages. In Study 1, children quoted themselves more frequently than any other speaker, and their mothers more frequently than their fathers. Directives were the most commonly reported speech act from the distant past in both older (Study 1) and younger (Study 2) children. In Study 1, girls used reported speech more frequently than did boys, and their quotations were more direct in form than were those of boys.

The use of Italian morphology was examined in 34 children ranging in age from 2;6 to 5;0. By the age of 3;6–4;0, high percentages of use in obligatory contexts were seen for a number of grammatical morphemes. Children age 2;6–3;0 showed percentages of use that were somewhat lower than those seen for the older children. In this age range, singular forms were used with higher percentages in obligatory contexts than plural forms, for several different types of grammatical morphemes. Greater control over singular forms in these younger children was corroborated by data from a comprehension task. Even at the younger ages studied, use of grammatical morphemes did not seem influenced by whether phonological eues to agreement were present, or whether the grammatical morphemes were homonymous. Percentages for grammatical morphemes in the form of free-standing morphemes were somewhat lower than percentages for morphemes taking the form of inflections, suggesting that the obligatory nature of inflections in Italian may be a more influential factor than the amount of morphological information contained in a grammatical morpheme.

As shown by Bowerman (1986), it has proved remarkably difficult to find clear-cut interpretations of why children face problems with conditionals. The present study reassesses a part of this puzzle by analysing four- to eight-year-old French children's acquisition of conditional verb forms. Relevant data in the literature and results of an experiment designed to gain information on the temporal meaning of young children's past conditional verb forms are presented and discussed. Among others, they are shown to provide weak support for interpretations stressing the role of conceptual problems and related mapping problems. Meeting one of Slobin's (1985) proposals, an interpretation is suggested that views the lateness of the past conditional verb form as due to an unexpected juxtaposition of ‘possibility’ and ‘non-possibility’ in its semantic representation. It is argued that such a juxtaposition cannot be achieved on the sole basis of cognitive development and that it requires the preliminary mastery of the conditional verb form.

An infant girl's unusual phonological behaviour was evaluated in the light of a maternai model which appeared to exaggerate features of normal conversational speech. It is suggested that parental responses to immature speech patterns may account for selected case study behaviours which have been reported in both the child phonology and child fluency literatures. It appears that evaluation of phonological development within an interactive framework may allow a more accurate picture of the conditions under which children learn speech skills. To this end, further study of the phonetic characteristics of input language and patterns of parental feedback to early articulatory attempts is desirable.

Poems were elicited from 133 English children between two and six and 171 Italian children between three and seven, using a similar technique, and the results were compared. Both groups produced large numbers of poems. There were great similarities and some differences. The majority of poems in both samples contained phonological devices (mostly rhyme and alliteration) and the proportion was higher (87%) in the Italian sample than in the English sample (59%). The proportion of poems that contained rhyme was close to 45% in each sample, with no consistent age difference in either sample. About one-third of Italian poems and just over a fifth of English poems contained alliteration. The frequency of alliteration declined with age in the English sample but not in the Italian sample. Possible reasons for the differences between the samples are considered. It is argued that the similarities are more important, and their theoretical implications are discussed.

This research examines whether infants actively seek information from a speaker regarding the referent of the speaker's utterance. Forty-eight infants (in three age groups: 1;2–1;3, 1;4–1;5, and 1;6–1;7) heard novel labels for novel objects in two situations: follow-in labelling (the experimenter looked at and labelled the toy of the infant's focus) vs. discrepant labelling (the experimenter looked at and labelled a different toy than that of the infant's focus). Subsequently, half of the infants were asked comprehension questions (e.g. ‘Where's the peri?’). The other half were asked preference questions (e.g. ‘Where's the one you like?’), to ensure that their comprehension performance was not merely the result of preferential responding. The comprehension results revealed developmental change in both (a) infants' ability to establish new word-object mappings (infants aged 1;2–1;3 failed to establish stable word-object links even in follow-in labelling), and (b) infants' ability to pinpoint the correct referent during discrepant labelling (only infants aged 1;6–1;7 succeeded). Thus the period between 1;2 and 1;7 represents a time of change in infants' ability to establish new word-object mappings: infants are becoming increasingly adept at acquiring new labels under minimal learning conditions.

Do infants and young children (two-year-olds) possess an implicit theory of mind which is revealed through their communicative interactions or are they simply treating their interlocutors as objects to manipulate in service to their own material ends? Shatz & O'Reilly (1990) criticized a paper by Golinkoff (1986) for claiming that infants were attempting to communicate as opposed to simply manipulate their listeners. This paper takes exception to that argument. It reviews additional evidence which indicates that infants in the second year of life are capable of communicating for the sake of the ‘meeting of minds’. The alternative – treating young children's communications as only the firing off of conversational routines for the purpose of attaining material ends – seriously underestimates infants' knowledge of the communicative process.

We examined whether children rely on linguistic information (i.e. mass vs. count nouns) or object category information (i.e. objects vs. substances) when they name things. A grinder test was used, in which substances (e.g. water) maintain identity through transformation but objects (e.g. a cup) do not. Thirty children aged three through six were asked if the same name could be used for the same item after transformation. The items included pairs of amorphous substances and discrete objects (e.g. water – a cup), perceptually similar discrete objects (e.g. chalk – a crayon), and food items (e.g. corn – a bean). Children accepted the same name for food, ignoring linguistic information, and for objects, relying on linguistic information. In Experiment 2, 32 children aged five through eight were asked if the same name could be used for unfamiliar hardware and food items after transformation when they were labelled by nonsense mass and count nouns. Children tended to use the same name for food, relying on perceptual information. These results are discussed in terms of the active conceptualization about names of objects in relation to object characteristics.

In Pizzuto & Caselli (1992, hereafter: P&C) we provided an overview of morphological development in Italian, focusing on three aspects of free speech production (verbs, pronouns and articles), in the longitudinal records of three children. We analysed our data using criteria appropriate to allow reliable cross-linguistic comparisons with data from English. By this means we evaluated the plausibility of a nativist, parameter-setting account of language development in Italian and English, as proposed for these two languages by Hyams (1986a b; 1987; 1988). We concluded that our data did not support the strong predictions made within such a parameter-setting account, and that the developmental patterns observed were best explained by a combination of cognitive, perceptual and distributional factors of the sort that are proposed in most other models of language acquisition.

Twenty-two normally developing five-year-olds were asked to judge, identify, repair and explain phonological and morphological errors. All of the errors involved the addition, substitution or omission of a single phoneme, which in the morphological task, was also an inflectional morpheme. Stimuli were controlled for type of error (omission, addition, substitution), location of the error (word final) and word status of the resulting error (word, non-word). Children performed significantly better on the phonological task than on the morphological task. It is proposed that the results are due to differences in the type and location of linguistic information to be analysed and to differences in memory demands in the tasks.

Edwards (1992c) concerns data and data use rather than manuals. It presents principles to facilitate reliable archive research in an imperfect world. MacWhinney & Snow (1992) endorse the principles but disagree on important details, discussed in this response. M&S underrate the impact of corpus inconsistencies on substantive conclusions. Since acquisition research concerns events which often trickle in a few at a time, main findings often involve a handful of examples, so overlooking a single early variant can seriously skew results. Until archives become perfect, if they do, type-token listings can help in identifying variants before computer search and avoiding this hazard.

The purpose of this study was to explore the relation between joint picture-book-reading experiences provided in the home and children's early oral language skills. Subjects were 41 two-year-old children and their mothers. Measures included maternal report of the age at which she began to read to the child, the frequency of home reading sessions, the number of stories read per week, and the frequency of visits by the child to the local library. Measures of language skill used were the child's receptive and expressive scores on the revised Reynell Developmental Language Scales. Multiple regression analyses indicated that picture-book reading exposure was more strongly related to receptive than to expressive language. Age of onset of home reading routines was the most important predictor of oral language skills. Directions of effect, the importance of parental beliefs as determinants of home reading practices, and the possible existence of a threshold level for reading frequency are discussed.