This article examines D. Gentner's (1982) claim that nouns are universally predominant in children's early vocabularies. When a conservative method of counting nouns was used, 9 out of 10 22month-old monolingual Mandarin-speaking children produced more verbs or action words than nouns or object labels in their naturalistic speech. When a more liberal definition of nouns was used, neither a noun nor a verb bias was found. Importantly, there was no difference in the type-token ratios of the children's use of nouns and verbs. Thus, a sampling bias type of explanation cannot explain the prevalence of verbs in these data. Instead, these data suggest the importance of a variety of linguistic and sociocultural input factors in early word learning. I thank Jing Qicheng, Leng Lixing, and Niu Weihua at the Institute of Psychology, Chinese Academy of Sciences, Beijing, China, for their help in arranging and carrying out this study, as well as the Beijing children and families who participated.

This paper examines naturalistic samples of adult-to-child speech to determine if variations in the input are consistent with reported variations in the proportions of nouns and verbs in children's early vocabularies. It contrasts two PRO-DROP languages, Italian and Mandarin, with English. Naturalistic speech samples from six 2;0 English-, six 1;11 Italian-, and ten 1;10 Mandarin-speaking children and their caregivers were examined. Adult-to-child speech was coded for the type frequency, token frequency, utterance position, and morphological variation of nouns and verbs as well as the types and placements of syntactic subjects and the pragmatic focus of adult questions. Children's spontaneous productions of nouns and verbs and their responses to adult questions were also examined. The results suggest a pattern consistent with the children's spontaneous production data. Namely, the speech of English-speaking caregivers emphasized nouns over verbs, whereas that of Mandarin-speaking caregivers emphasized verbs over nouns. The data from the Italian-speaking caregivers were more equivocal, though still noun-oriented, across these various input measures.

Recently, researchers have been debating whether children exhibit a universal "noun bias" when learning a first language. The present study compares the proportions of nouns and verbs in the early vocabularies of 24 English-and 24 Mandarin-speaking toddlers ( M age ϭ 20 months) and their mothers. Three different methods were used to measure the proportion of noun types, relative to verb types: controlled observations in three contexts (book reading, mechanical toy play, regular toy play), identical across languages; a vocabulary checklist (MacArthur Communicative Development Inventory); and mothers' reporting of their children's "first words." Across all measures, Mandarin-speaking children were found to have relatively fewer nouns and more verbs than English-speaking children. However, context itself played an important role in the proportions of nouns found in children's vocabularies, such that, regardless of the language spoken, children's vocabularies appeared dominated by nouns when they were engaged in book reading, but not when they were playing with toys. Mothers' speech to children showed the same language differences (relatively more verbs in Mandarin), although both Mandarin-and English-speaking mothers produced relatively more verbs than their children. In sum, whether or not language-learning toddlers demonstrate a "noun bias" depends on a variety of factors, including the methods by which their vocabularies are sampled and the contexts in which observations occur.

Theory of mind is claimed to develop universally among humans across cultures with vastly different folk psychologies. However, in the attempt to test and confirm a claim of universality, individual studies have been limited by small sample sizes, sample specificities, and an overwhelming focus on Anglo- European children. The current meta-analysis of children's false-belief performance provides the most comprehensive examination to date of theory-of-mind development in a population of non-Western children speaking non-Indo-European languages (i.e., Mandarin and Cantonese). The meta-analysis consisted of 196 Chinese conditions (127 from mainland China and 69 from Hong Kong), representing responses from more than 3,000 children, compared with 155 similar North American conditions (83 conditions from the United States and 72 conditions from Canada). The findings show parallel developmental trajectories of false-belief understanding for children in China and North America coupled with significant differences in the timing of development across communities-children's false-belief performance varied across different locales by as much as 2 or more years. These data support the importance of both universal trajectories and specific experiential factors in the development of theory of mind.