Purpose: The relatedness of tense morphemes in the language of children younger than 3 years of age is a matter of controversy. Generativist accounts predict that the morphemes will be related, whereas usage-based accounts predict the absence of relationships. This study focused on the increasing productivity of the 5 morphemes in the tense…

Purpose: Theories of morphosyntactic development must account for between-child differences in morphosyntactic growth rates. This study extends Legate and Yang's (2007) theoretically motivated cross-linguistic approach to determine if variation in properties of parent input accounts for differences in the growth of tense productivity. Method:…