An acquisition of agreement features: Lithuanian adjectives

Abstract

Lithuanian adjectives constitute a well-defined morphological category: they are inflected and fall into nine declensions. Lithuanian adjectives agree with nouns in number, gender, and case. Despite rich inflectional system, Lithuanian adjectives are morphologically similar to nouns: they behave much like nouns and their declensions are practically the same. The similarity between the paradigms of nouns and adjectives facilitates an acquisition of agreement features. Despite this fact, some errors in agreement were observed in the speech of the children. The aim of the research was to identify the key problems of adjective agreement across different cases of Lithuanian language acquisition. The study was based on a large longitudinal corpus data containing speech samples of children with different history of language acquisition. The data included speech samples of two typically-developing (TD) children, an early talker, a late talker, a low SES child, and a pair of twins. (The study was supported by a grant No. LIP-020/2016 from the Research Council of Lithuania.) The results evidenced that the first adjective correct agreement occurred: 1 month after the 1st adjective emergence in the TD children, the early talker, and the late talker; 3 months after the 1st adjective emergence in the twins; and 6 months after the 1st adjective emergence in the low SES child. Moreover, 5-7% of adjectives in the TD, 10-30% of adjectives in the twins, and 30% of adjectives in the low SES child contained erroneous agreement. To sum up, the TD children, early talkers, and even late talkers did not face with difficulties in acquisition of adjective agreement. This confirms the claim that inflections in languages with rich morphology are more easily acquired in contrast to languages with poor morphology. However, adjective agreement causes particular difficulties for twins and low SES children. [...]