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.

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.

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.

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.

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.

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.

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.

Pre-school children's comprehension of the adverbial modifiers very and sort of, when combined with two pairs of polar dimensional adjectives (big/little and tall/short) was experimentally investigated in 64 children (three, four and five years of age). The task involved the choice of an item from a graduated array of nine objects in response to questions combining the modifiers and adjectives. Results suggested that comprehension of very begins in the third year and is understood consistently by the four- and five-year-olds in combination with all four adjectives. Sort of is not understood by the three-year-olds, but appears to be available to the four- and five-year-olds. Results are interpreted as a reflection of an early appreciation that linguistic categories are not well bounded.

Two groups of preschoolers and one group of young grade-schoolers were tested for their comprehension of presuppositions and negation in complex syntax. Four types of sentences were presented to each child: affirmative and negative versions of sentences with factive main predicates, which presuppose the truth of the proposition of the complement clause, and nonfactive main predicates, which do not. A forced-choice design was used: the children chose the agent subject mentioned in the complement clause, thus affirming the complement; or the unmentioned agent, thus denying the complement. Five factive predicates and five non-factive predicates were used so as to permit a comparison within each group. Competence increased into the early school years: the oldest group of participants showed a fair mastery of the syntax-semantics of the predicates of the study. The younger children showed errors of two different kinds, described as the Overextended Negation Tendency and the Overextended Affirmation Tendency. Both of these errors decreased markedly in the oldest group. The non-unitary nature of the acquired competence is discussed. In particular, it is pointed out that (1) factivity is not a grammatically marked operation and as such leads to what appears to be a gradual acquisition pattern; (2) the test of factivity comprehension employed here demanded a competence beyond that of normal use.

Analysing the gradual learning process through which a child becomes bilingual from early infancy, three stages can be distinguished: (1) the child has one lexical system which includes words from both languages; (2) the child distinguishes two different lexicons but applies the same syntactic rules to both languages; (3) the child has two linguistic codes, differentiated both in lexicon and in syntax, but each language is exclusively associated with the person using that language. Only at the end of this stage, when the tendency to categorize people in terms of their language decreases, can one say that a child is truly bilingual.

Language samples of five Spanish/English bilingual children between the ages of 2; 10 and 6; 2 were examined for language mixes. Only 2% of the total utterances examined contained mixes. The most common type of mix involved the insertion of single lexical entries – mostly English nouns into Spanish utterances. Very few phrasal mixes were observed. It was concluded that language mixes do not constitute a major interference in the acquisition of bilingualism since children appear to be able to differentiate their two linguistic systems from an early age.