Since this is the last issue which I shall edit for the Journal, I would like to express my thanks to authors, reviewers and members of the Editorial Board, to Patrick McCartan and Gwenda Edwards at CUP and to Clive Jenkins, the copyeditor, for their efforts over the past nine years. Very special thanks go to the team of Associate Editors, past and present, the book reviews editor, the statistics consultant and Jo Lewis, the editorial assistant, who has worked with me for almost the entire period of my editorship. Their commitment to the Journal and our discipline and their hard work has made the job not only possible but also enjoyable.

Previous work on the acquisition of consonant clusters points to a tendency for word-final clusters to be acquired before word-initial clusters (Templin, 1957; Lleó & Prinz, 1996; Levelt, Schiller & Levelt, 2000). This paper evaluates possible structural, morphological, frequency-based, and articulatory explanations for this asymmetry using a picture identification task with 12 English-speaking two-year-olds. The results show that word-final stop+/s/ clusters and nasal+/z/ clusters were produced much more accurately than word-initial /s/+stop clusters and /s/+nasal clusters. Neither structural nor frequency factors are able to account for these findings. Further analysis of longitudinal spontaneous production data from 2 children aged 1;1–2;6 provides little support for the role of morphology in explaining these results. We argue that an articulatory account best explains the asymmetries in the production of word-initial and word-final clusters.

Thirty middle- to upper middle-class monolingual Dutch speaking families consisting of at least a mother and a father completed the Infant Form ‘Words and Gestures’ of the Dutch adaptation of the MacArthur Communicative Development Inventory for the same child at 1;1. Considerable inter- and intrafamily variation emerged in how two (or three) different reporters who are all presumably close to the child assess a particular child's communicative abilities. The greater the child's communicative ability, as rated by any one reporter, the more differences tended to emerge between reporters. In order to take into account multiple reporters' assessments of the same child, we propose the use of a Cumulative CDI Score that credits the child with the best score for any item on the CDI as checked by any single reporter. We conclude that single reporter CDI reports may underestimate the child's communicative knowledge.

The relationship between grammatical and lexical development was compared in 233 English and 233 Italian children aged between 1;6 and 2;6, matched for age, gender, and vocabulary size on the MacArthur Communicative Development Inventories (CDI). Four different measures of Mean Length of Utterance were applied to the three longest utterances reported by parents, and to corrected/expanded versions representing the ‘target’ for each utterance. Italians had longer MLUs on most measures, but the ratio of actual to target MLUs did not differ between languages. Age and vocabulary both contributed significant variance to MLU, but the contribution of vocabulary was much larger, suggesting that vocabulary size may provide a better basis for crosslinguistic comparisons of grammatical development. The relationship between MLU and vocabulary size was non-linear in English but linear in Italian, suggesting that grammar ‘gets off the ground’ earlier in a richly inflected language. A possible mechanism to account for this difference is discussed.

Two construals of agency are evaluated as possible innate biases guiding case-marking in children. A BROAD construal treats agentive arguments of multi-participant and single-participant events as being similar. A NARROWER construal is restricted to agents of multi-participant events. In Hindi, ergative case-marking is associated with agentive participants of multi-participant, perfective actions. Children relying on a broad or narrow construal of agent are predicted to overextend ergative case-marking to agentive participants of transitive imperfective actions and/or intransitive actions. Longitudinal data from three children acquiring Hindi (1;7 to 3;9) reveal no overextension errors, suggesting early sensitivity to distributional patterns in the input.

The goal of this research is to determine the relevant factors that aid in the acquisition of the perfective aspect in Russian. Results confirm the findings of previous research, which say that aspect is not learned as a uniform category, but rather interrelates with the acquisition of Aktionsarten. This study focuses on the factors responsible for the difference in the rate of the acquisition of two complementary Aktionsarten in the perfective aspect: telic verbs (verbs including a result/goal of the denoted event) and ingressive verbs (verbs including the beginning of the event).

Since the usage of Aktionsarten strongly depends on the surrounding discourse, two experiments that varied in their discourse complexity were conducted. One study looked at the production of isolated utterances (thirty-nine children aged 3;0 to 6;11) and the other study focused on complex texts (fifty-two children aged 3;0 to 6;11). It was found that while telics are used independently of discourse context, ingressives depend strongly on contextual information.

These results suggest that discourse complexity and narrative competence define the acquisitional process for ingressives, yet are irrelevant in the acquisition of telics.

This study compares homonym learning to novel word learning by three- to four-year-old children to determine whether homonyms are learned more rapidly or more slowly than novel words. In addition, the role of form characteristics in homonym learning is examined by manipulating phonotactic probability and word frequency. Thirty-two children were exposed to homonyms and novel words in a story with visual support and learning was measured in two tasks: referent identification; picture naming. Results showed that responses to homonyms were as accurate as responses to novel words in the referent identification task. In contrast, responses to homonyms were more accurate than responses to novel words in the picture-naming task. Furthermore, homonyms composed of common sound sequences were named more accurately than those composed of rare sound sequences. The influence of word frequency was less straightforward. These results may be inconsistent with a one-to-one form–referent bias in word learning.

This paper reports on an investigation of children's (aged 3;5–9;8) comprehension of sentences containing ambiguity of prepositional phrase (PP) attachment. Results from a picture selection study (N=90) showed that children use verb semantics and preposition type to resolve the ambiguity, with older children also showing sensitivity to the definiteness of the object NP as a cue to interpretation. Study 2 investigated three- and five-year-old children's (N=47) ability to override an instrumental interpretation of ambiguous PPs in order to process attributes of the referential scene. The results showed that while five-year-olds are capable of incorporating aspects of the referential scene into their interpretations, three-year-olds are not as successful. Overall, the results suggest that children are attuned very early to the lexico-semantic co-occurrences that have been shown to aid ambiguity resolution in adults, but that more diffuse cues to interpretation are used only later in development.

Two studies investigating young readers' use of conjunctions are reported. In Study One, 145 eight- to ten-year-olds completed one of two narrative cloze tasks in which different types of conjunction were deleted. Performance for additive conjunctions was not affected by age in this study, but older children were more likely to select the target conjunction than were younger children for temporal, causal, and adversative terms. Performance was superior in the cloze task in which they were given a restricted choice of responses (three vs. seven). In Study Two, 35 eight- and nine-year-old good and poor comprehenders completed the three-choice cloze task. The poor comprehenders were less likely to select the target terms in general. Sentence-level comprehension skills did not account for their poor performance. The results indicate that understanding of the semantic relations expressed by conjunctions is still developing long after these terms are used correctly in children's speech. The findings are discussed in relation to the role of conjunctions in text comprehension.

This study investigates subject omission in six English-Inuktitut simultaneous bilingual children, aged 1;8–3;9, to examine whether there are cross-language influences in their language development. Previous research with other language pairs has shown that the morphosyntax of one language can influence the development of morphosyntax in the other language. Most of this research has focused on Romance-Germanic language combinations using case studies. In this study, we examined a language pair (English-Inuktitut) with radically different morphosyntactic structures. Analysis of the English-only and Inuktitut-only utterances of the children revealed monolingual-like acquisition patterns and subject omission rates. The data indicate that these bilingual children possessed knowledge of the target languages that was language-specific and that previously identified triggers for crosslinguistic influence do not operate universally.

The aim of the study presented here was to examine variations in the forms and functions of agreement and refusal messages – which can be solely gestural, solely verbal, or combined gestural and verbal – by thirty children aged 1;4, 2;0, and 3;0 (ten in each age group) observed at home during an interaction with their mother. The results showed that even though verbal forms were the predominant ones as a whole, gestural forms were carried over into the linguistic period, and for the youngest children, constituted the sole means of agreeing and refusing. They also showed that the most frequently expressed function was assertion.