Words have meanings vastly undetermined by the contexts in which they occur. Their acquisition therefore presents formidable problems of induction. Lila Gleitman and colleagues have advocated for one part of a solution: indirect evidence for a word’s meaning may come from its syntactic distribution, via syntactic bootstrapping. But while formal theories argue for principled links between meaning and syntax, actual syntactic evidence about meaning is noisy and highly abstract. This paper examines the role that syntactic bootstrapping can play in learning modal and attitude verb meanings, for which the physical context is especially uninformative. I argue that abstract syntactic classifications are useful to the child, but that something further is both necessary and available. I examine how pragmatic and syntactic cues can combine in mutually constraining ways to help learners infer attitude meanings, but need to be supplemented by semantic information from the lexical context in the case of modals.

Syntactic bootstrapping is based on the premise that there are probabilistic correspondences between the syntactic structure in which a word occurs and the word’s meaning, and that such links hold, with some degree of generality, cross-linguistically. The procedure has been extensively discussed with respect to verbs, where it has been proposed as a mechanism for constraining the massive ambiguity that arises when inferring the meaning of a verb that is used to describe an event (Fisher, Hall, Rakowitz & Gleitman, 1994; Gleitman, 1990; Gleitman, Cassidy, Nappa, Papafragou & Trueswell, 2005). In her keynote paper (Hacquard, 2022), Hacquard focuses on classes of verbs for which inferences about meaning are arguably even harder, because they involve concepts that have no observable counterparts: these are attitude verbs such as think and want, and modals such as must and can. She walks us through, in meticulous detail, the limits of a purely syntactic bootstrapping mechanism, and she describes how augmenting syntactic information with pragmatic information, via pragmatic syntactic bootstrapping (Hacquard, 2022; Hacquard & Lidz, 2019), might address these limitations. The proposal is exciting, and the detail with which Hacquard works through these examples is impressive; she supports her arguments with behavioral experiments, corpus analyses, and two very targeted computational analyses. In this commentary I suggest that Hacquard’s proposal is laid out in sufficient detail such that a comprehensive computational modeling effort would be fruitful for evaluating and further developing her account.

Like verbs, adjectives pose a challenge to the young word learner in that some – like red, round, rough, or rectangular – map onto properties that are detectable through the senses, while others – like ready, reasonable, or required – express abstract properties that have no reliable, physical correlate. Even for those adjectives whose properties are observable, how does a child know that one particular property is being highlighted above all others? The physical environment alone will not suffice. Just as with verbs, the child learning adjectives is faced with an inherent indeterminacy of meaning, which can only be resolved through the incorporation of cues originating from multiple sources.

In ‘Being pragmatic about syntactic bootstrapping’, Hacquard (2022) argues that abstract syntax is useful for word learning, but that an additional cue, pragmatics, is both necessary and available for young children during the first steps of language acquisition. She focuses on modals and attitude verbs, where the physical context seems particularly impoverished as the sole basis for deriving meanings, and thus where linguistic cues may be particularly helpful. She convincingly shows how pragmatic and syntactic cues could be combined to help young language learners learn and infer the possible meanings of attitude verbs such as “think”, “know” or “want”. She also argues that, in some circumstances, syntax and pragmatics would need to be supplemented by semantic information from context – for instance, in the case of modals such as “might”, “can”, or “must”. We agree with Hacquard on the importance of the synergies between these different cues to meaning, and wish to add two other aspects of the input that might also be used by young children in these contexts. The aspects we describe can only be noticed when one analyzes concrete examples of what children hear in their everyday lives, something which Hacquard does very often in her work (e.g., Dieuleveut, van Dooren, Cournane & Hacquard, 2022; Huang, White, Liao, Hacquard & Lidz, 2022; Yang, 2022). Taking into account different cues for meaning would help the field go beyond current models of syntactic bootstrapping, and create an integrated picture of the synergies between different levels of linguistic information.

Meaning comes in different shapes and sizes. Content words like parrot and persimmon and perambulate convey some important – and very specific – kinds of meanings. But the kinds of meaning that syntactic structures encode are of a different sort. They are more general and abstract than those kinds of words, and they are linked to the underlying organization of language. The essential insight behind syntactic bootstrapping is that children can leverage the way that structural elements connect to abstract meanings to help them acquire the more specific kinds of meanings in the content words.

An emergent debate surrounds the nature of language processing in bilingual children as an extension of broader questions about their morphosyntactic development in comparison to monolinguals, with the picture so far being nuanced. This paper adds to this debate by investigating the processing of morphosyntactically complex which–questions (e.g., Which bear is chasing the camel?) using the visual world paradigm and is the first study to examine the online processing of such questions in bilingual children. For both groups, object which-questions were more difficult than subject which-questions, due to an initial misinterpretation that needed to be reanalysed. Both groups were aided by number mismatch between the two nouns in the sentence, especially in object which-questions. Our findings are in line with previous studies that have shown a slower processing speed in bilingual children relative to monolinguals but qualitatively similar patterns.

Debate around inflectional morphology in language acquisition has contrasted various rule- versus analogy-based approaches. This paper tests the rule-based Tolerance Principle (TP) against a new type of pattern in the acquisition of the possessive suffix -im in Northern East Cree. When possessed, each noun type either requires or disallows the suffix, which has a complex distribution throughout the lexicon. Using naturalistic video data from one adult and two children – Ani (2;01–4;03) and Daisy (3;08–5;10) – this paper presents two studies. Study 1 applies the TP to the input to extrapolate two possible sets of nested rules for -im and make predictions for child speech. Study 2 tests these predictions and finds that each child’s production of possessives over time is largely consistent with the predictions of the TP. This paper finds the TP can account for the acquisition of the possessive suffix and discusses implications for language science and Cree language communities.

This study investigates the influence of the quantity, content, and context of screen media use on the language development of 85 Saudi children aged 1 to 3 years. Surveys and weekly event-based diaries were employed to track children’s screen use patterns. Language development was assessed using JISH Arabic Communicative Development Inventory (JACDI). Findings indicate that the most significant predictor of expressive and receptive vocabulary in 12- to 16-month-olds was screen media context (as measured by the frequency of interactive joint media engagements). In older children (17- to 36-month-olds), more screen time (as measured by the amount of time spent using screens, the prevalence of background TV at home, and the onset age of screen use) had the highest negative impact on expressive vocabulary and mean length of utterance. These findings support health recommendations on the negative effects of excessive screen time and the positive effects of co-viewing media with children.

The aim of this study was to investigate the acoustic vowel space area in infant directed speech (IDS). The research question is whether the vowel space is expanded or remains constant in IDS. A corpus of spontaneous interactions of 9 dyads followed monthly from the age of 6 to 24 months was analyzed. The occurrences in the parents’ speech of each word that the children eventually acquired were extracted. The surface of the vowel triangle and the convex hull of all vowels were computed. The main result is that the development of the vowel space in IDS follows an inverted U-shaped curve: the vowel space starts relatively small, gradually increases as the child’s first word use approaches, and decreases again afterwards. These findings show that parents adapt their articulation to the evolving linguistic abilities of their child, and this adaptation can be detected at the level of individual lexical items.

Children’s exposure to talk about conceptual categories plays a powerful role in shaping their conceptual development. However, it remains unclear when parents begin to talk about categories with young children and whether such talk relates to children’s language skills. This study examines relations between parents’ talk about conceptual categories and infants’ expressive language development. Forty-seven parent-infant dyads were videotaped playing together at child age 10, 12, 14, and 16 months. Transcripts of interactions were analyzed to identify parents’ talk about conceptual categories. Children’s expressive language development was assessed at 18 months. Findings indicate that parents indeed talked about conceptual categories with infants and that talk was stable across time, with college-educated parents producing more than non-college-educated parents. Further, parents’ talk about conceptual categories between 10 and 16 months predicted children’s 18-month expressive language. This study sheds new light on mechanisms through which early experiences may support children’s language development.

This study investigates how Japanese-speaking children learn interactional dependencies in conversations that determine the use of un, a token typically used as a positive response for yes-no questions, backchannel, and acknowledgement. We hypothesise that children learn to produce un appropriately by recognising different types of cues occurring in the immediately preceding turns. We built a set of generalised linear models on the longitudinal conversation data from seven children aged 1 to 5 years and their caregivers. Our models revealed that children not only increased their un production, but also learned to attend relevant cues in the preceding turns to understand when to respond by producing un. Children increasingly produced un when their interlocutors asked a yes-no question or signalled the continuation of their own speech. These results illustrate how children learn the probabilistic dependency between adjacent turns, and become able to participate in conversational interactions.

Voice onset time (VOT) of aspirated stop consonants is marked by variability and systematicity in adult speech production. The present study investigated variability and systematicity of voiceless aspirated stop VOT from 161 two- to five-year-old talkers of American English and Cantonese. Overall, many aspects of child VOT productions parallel adult patterns, the analysis of which can help inform our understanding of early speech production. For instance, VOT means were comparable between children and adults, despite greater variability. Further, across children in both languages, talker-specific VOT means were strongly correlated between [th] and [kh]. This correlation may reflect a constraint of “target uniformity” that minimizes variation in the phonetic realization of a shared distinctive feature. Therefore findings suggest that target uniformity is not merely a product of a mature grammar, but may instead shape speech production representations in children as young as two years of age.

Producing word-initial /s/-stop clusters can be a challenge for English-speaking pre-schoolers. For children with hearing loss (HL), fricatives can be also difficult to perceive, raising questions about their production and representation of /s/-stop clusters. The goal of this study was therefore to determine if pre-schoolers with HL can produce and represent the /s/ in word-initial /s/-stop clusters, and to compare this to their normal hearing (NH) peers. Based on both acoustic and perceptual analysis, we found that children with HL had little /s/-omission, suggesting that their phonological representation of these clusters closely aligns with that of their NH peers.