The route to the derivational verb family in Hebrew: A psycholinguistic study of acquisition and development

A main challenge for language users is forging reliable relationships between words with shared components so that morphology as a system emerges from usage. For native Hebrew acquisition this means that learners acquire verbs as lexical entities, which form into a system based on Semitic roots and binyan conjugations. The Hebrew verb system is consequently organized by derivational families, where verbs in different binyan conjugations share the same root. This is illustrated by the k-t-b- based family containing katav ‘write’, nixtav ‘be written’, hixtiv ‘dictate’, huxtav ‘be dictated’, kitev ‘carbon copy [cc]’, kutav ‘be cc’ed’, and hitkatev ‘correspond’. The current study offers a systematic account of how Hebrew verb families and their components—verb lemmas, roots and binyan patterns—emerge and develop in structural and semantic terms, covering the long route from infancy to adulthood. The study is grounded in a large database (485,908 word tokens) compiled of the spoken and written productions of Hebrew-speaking toddlers, children, adolescents and adults. The study is presented in two parts. Part I describes the general characteristics of the study database with regards to the distributions of verbs, roots and binyan verb conjugations, focusing on developmental changes as indicators of the growth and consolidation of the verb lexicon. Part II presents the development of root-based verb derivational families in terms of family frequency, family size, family composition and the semantic coherence of families. Based on the empirical evidence in this paper, our main claim is that roots, binyan conjugations and derivational verb families are all emergent properties of the verb system as it develops in variegated communicative contexts.