Definitions as a window to the acquisition of relative clauses

Definitions that children provide can be a valuable measure of their syntax, and specifically, of their ability to produce relative-clauses. This research explored the acquisition of subject-, object-, and indirect-object-relative clauses in 121 Hebrew-speaking children aged 3;5-8;6. The children were asked to define 14 nouns, and their responses were collected and analyzed for various syntactic aspects. The main results were that children started using relative-clauses in their definitions at age 3;8, and their use of relative-clause increased consistently until they were 6-years-old. Retesting 38 of the 6-year-olds at age 8;6 indicated no differences in several syntactic measures between their production of relative clauses at age 6 and 8;6, suggesting that the ability to produce relative-clauses stabilizes around age 6. The participants made almost no grammatical errors at any of the ages, probably because they avoided the use of relative-clauses when they had not mastered them yet. In the early stages participants produced mainly headless relatives, and with age the use of a relative head increased. The acquisition of relative clauses was not related to the ability to embed or to the ability to use pronouns: these abilities existed already in the youngest age group and remained constant throughout the age groups.