Interaction between particles and word order in the comprehension and production of simple sentences in Japanese children.

English is a language that relies extensively on word order to signal grammatical roles and meaning of sentences. Although studies have heavily emphasized the role of word order for children learning English, there is little information re-garding children learning languages that rely less on word order and more on inflections and particles. Such data would be essential in formulating a language-universal theory of language acquisition. This article reports four experiments tapping comprehension, production, and imitation of simple Sentences in Japanese children between 2 and 6 years of age. Japanese children must learn a language that has a dominant subject-object-verb order yet that allows flexibility in word order due to postposed particles that signal grammatical role. Results across different tasks suggest that children learning Japanese show neither a strong reliance on word order nor on particles alone. Rather, they possess a bias for a matching between particles and the position in the sentence where they appear. c A theory of language development must