The acquisition of connective forms and the meaning relations between connected clauses in the development of complex sentences is described for four children from two to three years of age. The major results of the study include the developmental interactions between syntactic connectives and meaning relations, and between these interactions and the discourse environments in which they occurred. The first syntactic connective the children learned, and, was the most general: semantically, and was used to encode conjunction with all of the different conjunction meaning relations in the order Additive < Temporal < Causal < Adversative. Other connectives were semantically more specific, and were learned subsequently with different syntactic structures in the order Conjunction < Complementation < Relativization. These results are discussed in terms of FORM, relative linguistic complexity; CONTENT, the intersection of form with conceptual and semantic factors affecting acquisition; and USE, discourse cohesion.

Measures of pragmatic development for children in the second year of life were developed, based on a brief (30 minute) language sample and on structured elicitation conditions. When age is partialled out, number of pragmatic functions expressed is not statistically related to MLU, due to the fact that the number of functions grows steadily during the one-word and very early two-word phases. Performance on the structured imperative tasks also reflects development during this period, though performance on the declarative tasks does not. We conclude that the range of pragmatic functions in the second year is measurable and contributes information not provided by a measure of syntactic development such as MLU. Such information should prove useful for research on language and cognition in normal and language-impaired children.

A psycholinguistic experiment elicits highly reliable judgements from young English-speaking children aged 2; 6–3; 0 about illocutionary force of utterances presented in controlled contexts. Puppet play simulated extralinguistic features judged capable of constituting felicity conditions upon the illocutionary acts Request and Offer. The experimental data bear upon two questions: (1) What set of features, linguistic and pragmatic, constitute cues for the discrimination of illocutionary force by young children? (2) What is the lower developmental bound of the emergence of discrimination of illocutionary force for Requests and Offers? While grasp of illocutionary force for Offers was well-established by 2; 6, discrimination skills for Requests probably continues to develop between 2; 6 and 3; 0. Relevant pragmatic features are explicated, and a model of the comprehension of illocutionary force proposed in the light of the results.

A Reichenbach-type theory is proposed that accounts for a child's early system of temporal reference and relates it directly to the adult system. This theory makes predictions different from those of a competing theory, a strong decentring hypothesis. Experimental results and data from spontaneous speech are examined, and the predictions of the first theory are borne out: young English-speaking children express notions of temporal ordering as well as aspectual notions.

This paper reports on the acquisition of the voicing contrast in Mexican–Spanish word-initial stops. In Study 1, three monolingual children were recorded every two weeks for seven months, beginning when the children were about 1; 7. In Study 2, four monolingual children about 3; 10 were recorded once or twice. Two analyses were done. Instrumental analysis of the stop productions revealed that not even by age 3; 10 were the children consistently distinguishing between voiced–voiceless stop cognate pairs on the basis of adult-like voice-onset time characteristics. The spirantization analysis, however, more clearly revealed the children's phonological knowledge. Discussion focuses on the implications of the data for phonological development in general and for the phonological description of voicing in Spanish.

An investigation was made of the episodic structure of maternal speech to young children during a free-play session. The findings indicate that maternal speech was organized so as to provide a high degree of redundancy with regard to the referential component of speech. The beginning of episodes, in which the same object was repeatedly referred to, was clearly marked; furthermore speech inside episodes with a common referent was highly repetitive. All this suggests that maternal speech is organized in a way that increases the predictability in the child's language environment.

The present study explored children's perceptual capabilities with regard to the temporal acoustic cue of differential vowel duration, comparing children's perceptual identifications to those of adults. Three-year-old children, six-year-old children, and adults participated in two experiments, in which they were asked to identify (as voiced or voiceless) CVC words with uniformly voiceless final obstruents, but in which vowel duration was systematically varied. Children were also asked to identify a set of CONTROL stimuli, in which both closure voicing and vowel duration differences were present. Results indicate that both subject age and vowel duration of the TEST stimuli significantly affect identification responses. Adults and six-year olds evidence perceptual cross-over in their judgements for the TEST stimuli, while three-year-olds do not seem to change their identifications, regardless of variations in vowel duration. However, for both groups of children, the accuracy of identifications was greater for originally voiced stimuli on the CONTROL set of words, in which more than one potential cue to the voicing distinction was present. These results suggest that there is a complex and somewhat paradoxical relationship between developing production and perception which deserves further research. Children may consistently produce a phonetic difference (vowel duration) which they are unable to use as the SOLE perceptual cue for a phonological contrast.

Natural speech of 32 young children from 2; 0 to 3; 1 (1·97 to 6·38 in MLU) was studied for evidence of use of coordination (by and). Analyses of the structure of coordinative expressions reflected development in structural variants as well as amount of coordination. Analyses suggested that early forms of coordination in natural speech reflected the same constraints which had been suggested by previous study of these children's language through an experimental elicited imitation task. A basis for a developmental theory of acquisition of coordination is sketched.

This study demonstrates a striking absence of variability in the speech which mothers address to children of the same age within the 1- to 5-year range. Speech to children of 1; 0, 1; 8, 2; 3 and 5; 0 years was analysed for aspects of syntactic, semantic, pragmatic and discourse structure. Discriminant function analyses showed that the age of the child to whom a mother was speaking could be predicted very accurately from her speech. The rate at which mothers' speech changed was greatest when the children were 1; 8–2; 3, and least when they were 2; 3–5; 0. These trends in the evolution of the maternal speech register are interpreted as responses to concurrent changes in children's language behaviour.

This paper reports on a longitudinal study of the acquisition of the voicing contrast in American English word-initial stop consonants, as measured by voice onset time. Four monolingual children were recorded at two-week intervals, beginning when the children were about 1; 6. Data provide evidence for three general stages: (1) the child has no contrast; (2) the child has a contrast but one that falls within the adult perceptual boundaries of one (usually voiced) phoneme and thus is presumably not perceptible to adults; and (3) the child has a contrast that resembles the adult contrast. The rate and nature of the developmental process are discussed in relation to two competing models for phonological acquisition and two hypotheses regarding the skills being learned.

This paper evaluates Lust's (1977) study of coordination in child language, both on its own merits and in the light of my own research. First, particular design weaknesses in Lust's study are noted which render her results questionable. In addition, it is argued that the hypotheses proposed by Lust fail to make any substantive predictions about the types of errors which children make with coordinate structures. Finally, it is shown that Lust's hypotheses cannot account for the results of my own comprehension and non-imitative production experiments. It is concluded that Lust cannot account for a wide range of phenomena concerning coordination in child language, and consequently an alternative set of hypotheses is proposed.

The speech of 36 mothers to their infants in a face-to-face situation at ages 6, 13 and 26 weeks was compared with unfamiliar adults' speech to the same infants, the mothers' speech to an interviewer, and their conversations with the same children 2 years later. Speech to the infants was quite different from so-called ‘baby talk’, but contrary to other authors the speech to infants was even shorter, more repetitive, and more limited in content than the speech to language-learning children. Differences appear due to the infant's changing status in the relationship, from a potential to an actual conversant.

The role of a strategy of reduplication in phonological acquisition and behaviour was examined in terms of: (1) the relationship between adoption of this strategy and children's failure to produce nonreduplicated multisyllabic forms and final consonants when attempting corresponding adult models; and (2) the role of the process of reduplication in production constraints. Comparisons of the phonologies of six children (1; 3–1; 9) classified as reduplicators and six children (1; 5–2; 0) classified as non-reduplicators revealed that the adoption/nonadoption of this strategy was closely related to the extent of production of nonreduplicated multisyllabic forms. Analyses of attempted words produced as reduplications revealed that this process served primarily to constrain multisyllabic productions. To a lesser degree, reduplication appeared to serve in conspiracies to constrain final consonant production.

This research explored overextension in the early vocabularies of six children, followed in a language diary study from 1; 0 to 1; 8. Results indicated that only one-third of the first 75 words acquired by each child were ever overextended. A small set of high-frequency, early acquired words accounted for a disproportionate number of overextensions. Overextensions were classified into three types: categorical overinclusions, analogical overextensions and predicate statements. Four types of information served as the bases for word applications: perceptual, action-functional, affective and contextual. The use of words to denote associative complexes of a well-organized, systematic character was discussed as a characteristic form of early word usage.

Several researchers (e.g. Bever 1970, Strohner & Nelson 1974) have suggested that young children commonly employ a word-order strategy of the form: ‘the first mentioned participant is agent’ when interpreting active and passive sentences. Pre-school children (aged 2; 6–5; 0) were presented with reversible active and passive sentences in four comprehension test settings (two acting-out tasks, a selection task and a verification task). Their responses were analysed not in terms of the percentage correct responses for each group of subjects, as has been the usual practice, but in terms of each individual child's pattern of responses. The results revealed age-related changes in the type of response patterns found. The response pattern associated with the word-order strategy was not a frequent occurrence. The most common patterns were those accounted for by extralinguistic cues such as the relative proximity, mobility or position of the referents. The significance of early interpretation rules of this sort for any characterization of young children's language comprehension processes is discussed.

Pronoun mastery demands a knowledge of speech roles and an ability to identify oneself and others in those roles. Twenty-one girls' (age 1; 6–2; 6) knowledge of my, your, and her was assessed when they were speakers, addressees and non-addressed listeners. My and your were at first understood correctly only when referring to the child's own speech role: your was comprehended when the child was addressed, though not produced correctly by the child; my was used by the child as speaker, while still not comprehended correctly when used by others. The first consistent production of her referred to dolls. Children thus were initially aware of speech roles, but only when they themselves occupied those roles.

The speech of four two-year-old children growing up bilingually in a German-speaking community was studied for periods varying between five and nine months. An analysis of their language mixing revealed an initially higher rate of mixing which diminished with a growth in language development as measured in MLU. The data suggest that the children were at various stages in a gradual process of language differentiation thus providing support for the one-system theory of bilingual acquisition. An examination of the distribution of lexical substitutions by part of speech revealed that nouns were most frequently substituted by all children; however, more function words were substituted than content words overall.

Two experiments were devised in order to better understand the relationship between temporal before and after and their spatial counterparts. In Experiment I, sixty adults were probed for their spatial metaphoric understanding of temporal before and after. Although H. Clark proposed that temporal before and after were derived from their spatial counterparts, Experiment I did not support that notion. In fact, the subjects overwhelmingly reported that temporal before was more related to spatial after and that temporal after was more related to spatial before. Since it has been shown by numerous investigators that temporal before is acquired before temporal after by children, the evidence from Experiment I suggested that their spatial relatives may be acquired similarly. Experiment II presents evidence that indeed spatial after is understood better by three-year-old children than spatial before. This evidence is coincident with the adult reports in Experiment I.

To evaluate Brown's assertion that frequency of input is not a significant variable in language acquisition, some of Brown's data were reanalysed. The data pertaining to Adam, Eve, Sarah and their parents were predominantly obtained from Brown's (1973) book and were supplemented from the transcripts. Parental input frequency and the children's age at mastery were highly related for each of the three triads. Then Sarah's input and rate of language acquisition were compared with that of the other two children. The correlation between Sarah's relative input deprivation and her relative linguistic delay was 0·66. Finally, an analysis of Eve's acquisition of specific prepositional phrases involving the preposition in were made. Again it was found that frequency of input was highly related to frequency of production. Detailed analyses of parent-child interactions provided evidence also for short-term effects of input frequency.