A longitudinal study of three children examined the relation between object permanence and language development. Unlike other studies, an independent measure of object permanence development was provided. While there was not a one-to-one correspondence between object permanence and language, there were relations at certain points in development. There was a rough relationship between the onset of stage 6 of object permanence and the onset of single-word utterances. Total vocabulary showed a large increase around the time of entrance into the preoperational period of object permanence development. At the same time, the semantic categories Nonexistence and Recurrence appeared. No differences were found in the use of function forms and substantive forms before object permanence development.

Vocalizations of two female infants, recorded over a 5-week period after the first emergence of cooing, were studied. The vocalizations were classified as cry, discomfort, vegetative and cooing (comfort) sounds. Fifty vocalizations of each sound type, distributed across the 5-week period of study, were selected from the output of each infant (400 vocalizations in all). The features of voicing, breath direction and consonant-like versus vowel-like were documented for each sound type. It was found that the features of the more primitive sound types regrouped themselves in comfort sounds. For the first time the feature of consonant-like was found to co-occur with voicing and egressive (outgoing) breath direction. The implications for theories of pre-speech development are discussed.

The achievement of labelling was investigated in a longitudinal study of one mother–infant dyad, using video-recordings of their free play in a period between 0; 8 and 1; 6. Analysis of joint picture-book reading revealed that this activity had very early on the structure of a dialogue. The child's lexical labels might be regarded as more adult-like substitutes for earlier communicative forms that he had utilized in the dialogue. These were smiling, reaching, pointing and babbling vocalizations, all of which were consistently interpreted by the mother as expressing the child's intention of requesting a label or providing one. Participating in a ritualized dialogue, rather than imitation, was found to be the major mechanism through which labelling was achieved.

The nature of early games and how they might assist the infant in language acquisition were explored in a longitudinal study of two mother–infant dyads, using video-recordings of their free play. Analysis of appearance and disappearance games, in particular, revealed: (1) a restricted format, with a limited number of semantic elements, and a highly constrained set of semantic relations; (2) a clear repetitive structure, which allowed both for anticipation of the order of events and variation of the individual elements; (3) positions for appropriate vocalizations which could in turn be used to mark variations; and (4) the development of reversible role relationships between mother and child.

Twelve one-word-stage children (aged 1; 4 to 2; 0) were given minimally contrasting two-word instructions, e.g. kiss duck, kiss car, bang duck and bang car. Since non-linguistic cues were eliminated, comprehension involved making non-syntactic inferences from the word combinations. The children could respond correctly to some of the instructions, and even carried out some unfamiliar activities such as tickle book. Observations of mother–child interactions revealed play routines that may help the child learn to understand more than one word at a time.

There have been relatively few studies on tone acquisition, as compared to studies on the acquisition of segmentals, morphology, and syntax. Still fewer are the studies on Chinese language acquisition. The present paper reports on a longitudinal case study of a Cantonese-speaking child aged 2; 8 and considers the implications of tone acquisition for tone studies in general, and Cantonese tonology in particular.

Child phonologists have made varying assumptions concerning the nature of phonological characteristics of children's imitative utterances and their relationship to the characteristics of spontaneous utterances. This study examined this relationship in children in early Stage I. A task was devised which permitted an inspection of children's unsolicited imitations of nonsense words reflecting syllabic shapes and consonants in and out of the child's phonological system. The results are discussed with respect to production constraints, phonological idioms, and selection and avoidance rules operative in imitative speech during this period of development. The findings indicated that while these imitative utterances were subject to the same production constraints they were not subject to the same selection and avoidance rules operative in spontaneous speech.

A common assumption underlying the semantic feature and the functional core hypotheses of lexical development is that attributes abstracted from the referents of a word are sufficient to determine the extension of that word. The present paper begins by challenging this assumption. A contrastive hypothesis is instead advanced to explain the early lexical development of children, and the predictions of this hypothesis are shown to be consistent with available data on overextension. The paper concludes with a critical discussion of the semantic feature and the functional core hypotheses in which it is shown that neither of these hypotheses can account for the data on overextension.

Children's imitations were analysed as a function of parental speech acts for six children in early Stage I of language acquisition. The relative frequency with which children imitated mothers reflected the relative frequency with which mothers imitated children (Spearman rank correlation = 0·77). Although parents' imitative expansions could all be categorized as having primary speech act functions (e.g. request for information) from the parents' point of view, expansions constituted a separate class of speech events in terms of children's responses. The children imitated imitations far more frequently than non-imitative speech acts in the same category. These findings suggest that individual differences in children's propensity to imitate may arise from the degree to which parents provide a model of imitation as a speech act.

Following Ferguson & Farwell (1975), this paper looks at phonological development in lexical terms and extends their method to consideration of syllables within words. Ferguson & Farwell dealt with word-initial consonants only; we attempt to determine whether the sets of phone classes in all positions are the same, whether differences that occur from position to position are primarily within the phone class or in the number and distribution of phone classes at each level in the tree, and what effect position in the syllable has on phone classes.

The development of two children's responses to yes/no questions is studied longitudinally. It will be proposed that the children realize that they must verbalize, but do not understand the semantics of the question form or the affirmative and negative particles. Their answers are not appropriate by the conventions of adult speech. In this situation, each child develops his own system, a phenomenon to be called PRAGMATIC VARIATION. Head nodding and shaking show a pattern of development comparable to that of the verbal responses. The options available to children acquiring English are discussed.

Much of adult communication is carried on at the subtle level of indirect utterance meaning, where the speaker's intent is not literally expressed in his or her utterance. This work investigates the young child's ability to respond appropriately to the intended, as opposed to the literal, meaning of one class of such utterances, requests for action. The data were the responses of five children between 1; 7 and 2; 4 to the direct and indirect requests for action their mothers produced during a natural play session. All the children responded with action to requests for it regardless of how subtly the requests were expressed. The apparent ability of two-year-olds to deal with indirect speech acts is surprising in that the understanding of such utterances by adults is presumed to depend on a combination of sophisticated rule systems. Rather than grant the young child such knowledge, the alternative of an action-based response heuristic is proposed.

The development of plurals in two German-speaking children was analysed, based on observational data. It was found that (1) plurals were supplied in 90% of the obligatory contexts somewhere between Stage IV and Stage V; (2) plurals were not functionally distinguished from singulars, occurring also in singular contexts; (3) the predominant morphological deviations were of the type in which an additional plural marker was attached to an already correct plural; (4) referring to a single object or event, formally correct plural utterances were often constructed, partly because of as yet unestablished verb conjugation rules. It was argued that the children were learning plurals by rote, conditioned by morphological complexity which cannot be subsumed under any general rule.

Although deictic terms are among the earliest words children acquire, the proximal/non-proximal contrast (the true deictic contrast) between here and there, and between this and that, takes several years to master. As research on spontaneous production shows, children may start, for example, by using here with a deictic meaning, there with a non-deictic meaning, and a gesture to indicate a deictic contrast. On the basis of two experiments on comprehension, we argue that children go through at least three stages in acquiring the deictic contrasts. They start with NO CONTRAST, work out a PARTIAL CONTRAST used only in certain contexts, and finally master a FULL CONTRAST equivalent to the adult's. However, children follow different routes through these stages, depending on their initial choice of (a) the point of reference for the contrast – themselves or the speaker – and (b) the spatial relation to that point of reference – proximity or distance.

This study investigated 3-, 5- and 7-year-old Tagalog-speaking children's mastery of agent-focus (active) and patient-focus (passive) sentence structures. In contrast to the usual English developmental pattern with actives and passives, the Tagalog children generally showed better mastery of patient-focus sentences than agent-focus sentences. These results were attributed to the children's strategy of interpreting the first noun of a sentence to be the agent of the action. The structure and usage of these sentence types in Tagalog do not appear to provide linguistic pressures favouring such a strategy. Thus these results are consistent with the view that such a strategy might be non-linguistic in origin.

51 children from 4; 11 to 8; 2 were given three words (a triplet made up of two nouns and one verb) and asked to produce an utterance with them. Words in the triplet were presented in every possible order. At all ages, the dominant responses to non-reversible triplets were utterances in which the animate noun served as the subject of the verb and the inanimate noun as its object, whatever the order of words within the triplet. Production of utterances in response to reversible triplets showed a clear differentiation with age (with the exception of responses to symmetrical triplets NVN for which the SVO structure is dominant at all ages). With non-symmetrical triplets (NNV or VNN), the strategy that assigns the function of subject to the first noun becomes progressively established. In the youngest children, a significant number of responses that preserve the order of stimulus elements is observed. This strategy results in attributing an identical grammatical function to the two nouns. As anticipated, isomorphism between stimulus structure and response structure diminishes with age.

Spontaneous full passives and related constructions from 234 children aged 2; 0 to 13; 11 and elicited passives from 262 college students were analysed. Full passives were classified as REVERSIBLE (The dog was chased by the girl), INSTRUMENTAL NON-REVERSIBLE (The lamp was broken by (or with) the ball), or AGENTIVE NON-REVERSIBLE (The lamp was broken by the girl). The Agentive non-reversible did not appear until after age 9; and until age 11 no child produced both Reversible and Non-reversible passives. All the children used the passive in a semantically restricted way (but not in the same way). The possible developmental course of the full passive was traced for children who initially used only Reversible passives versus those who initially used only Instrumental non-reversible passives.

Fifty children between the ages of 3; 0 and 5; 6 were asked six types of wh- questions following videotaped sequences. It is argued that differential difficulty of various forms of who questions supports a parallel model of information retrieval and processing during discourse. The differential difficulty of why and when questions are, however, attributable to a necessary progression in the ability to encode the relevant concepts linguistically. Responses to how questions are difficult because they involve a number of unrelated skills.

Sixty kindergartners and sixty first graders were given three tasks to test their comprehension of the terms before and after. The results show that when temporal terms are acquired, they are first used as prepositions and then as subordinating conjunctions. When the child does not know the meaning of a temporal term, he frequently interprets it as meaning the next-event-in-time. There are two strategies (main-clause-first and order-of-mention) that the child may adopt when interpreting temporal terms used as subordinating conjunctions. The use of these strategies appears to be independent of the child's knowledge of the meanings of the terms. Contrary to previous research, it was found that before does not seem to be learned before after nor does there appear to be any stage where after is treated to mean before.

To explore the relationship of language use and speech adaptation to role and context the spontaneous speech of a boy aged 5; 6 was recorded in three different situations: playing alone, playing with a friend of the same age, and playing with his mother. Several analyses were made of the speech transcripts to examine the relationship between context and language use. The nature of play episodes was also investigated. The findings suggest that role play has an important function in the development of a child's ability to communicate effectively, and that a child's awareness of his own role and the expectations he has concerning social interactions lead to modification in language use.