Toward mastery of Italian morphology: a cross-sectional study.

The use of Italian morphology was examined in 34 children ranging in age from 2;6 to 5;0. By the age of 3;6-4;0, high percentages of use in obligatory contexts were seen for a number of grammatical morphemes. Children age 2;6-3;0 showed percentages of use that were somewhat lower than those seen for the older children. In this age range, singular forms were used with higher percentages in obligatory contexts than plural forms, for several different types of grammatical morphemes. Greater control over singular forms in these younger children was corroborated by data from a comprehension task. Even at the younger ages studied, use of grammatical morphemes did not seem influenced by whether phonological cues to agreement were present, or whether the grammatical morphemes were homonymous. Percentages for grammatical morphemes in the form of free-standing morphemes were somewhat lower than percentages for morphemes taking the form of inflections, suggesting that the obligatory nature of inflections in Italian may be a more influential factor than the amount of morphological information contained in a grammatical morpheme.