The typical development of simultaneous bilinguals
This chapter focuses on the effect of the relative amount of exposure bilingual children have received in each of their languages on their performance on tests of language knowledge (vocabulary and grammar) and language processing (nonword repetition and sentence imitation). Results are reported on studies of two age groups of monolingual and bilingual preschoolers in Montreal, Canada, learning English and French. Amount of input exerted a strong effect on the rate of development of both vocabulary and grammar, but had little impact on children’s ability to repeat nonwords. Children with unequal amounts of exposure to each language had similarly unequal levels of performance both in vocabulary and grammar. Grammatical development followed strongly language specific patterns in terms of order of acquisition, accuracy and error types. Normative data are reported on bilingual children with different levels of exposure that aid in the language assessment of bilingual children. Nonword repetition accurately distinguished children with and without language impairment regardless of bilingual exposure.