This study investigated the relation between Dual Language Learners' (N = 90) vocabulary and grammar comprehension and word learning processes in preschool (aged 3-through-5 years). Of interest was whether: (a) performance in Spanish correlated with performance in English within each domain; and (b) comprehension predicted novel word learning…

This cluster-randomized controlled study examined dual language learners (DLLs) in Norway who received a book-based language intervention program. About 464 DLLs aged 3-5 years in 123 early childhood classrooms participated in the study. The children were acquiring Norwegian as their second language in preschool and spoke a variety of first…

In the last 50 years, researchers have debated over the lexical or grammatical nature of children's early multiword utterances. Due to methodological limitations, the issue remains controversial. This corpus study explores the effect of grammatical, lexical, and pragmatic categories on mean length of utterances (MLU). A total of 312 speech samples…

The purpose of this study was to empirically examine the dimensionality of language ability for young children (4-8 years) from prekindergarten to third grade (n = 915), theorizing that measures of vocabulary and grammar ability will represent a unitary trait across these ages, and to determine whether discourse skills represent an additional…

Recent accounts of language acquisition propose that the knowledge structures that comprise language develop within a single, unified system that shares computational resources and representations. One implication of this approach is that developmental relations within the system become central to theorizing about language acquisition. Previous…

Studies using the English and Spanish MacArthur Communicative Development Inventories demonstrated that the grammatical abilities of 20--30-month-old bilingual children were related more strongly to same-language vocabulary development than to broader lexical-conceptual development or maturation. First, proportions of different word types in each…

Two cohorts of same-sex twin pairs were assessed on grammar and vocabulary. Findings indicated that vocabulary and grammar correlated strongly at 2 and 3 years in both cohorts, with a consistently high genetic correlation between vocabulary and grammar at both ages. Findings suggest that the same genetic influences operate for vocabulary and…

Examined how child and family factors influence individual differences in the language development of African-American children between 18 and 30 months of age. Found that vocabulary and utterance length increased linearly. Children from more stimulating and responsive homes had larger vocabularies, used more irregular nouns and verbs, and had…