The Role of Parental Input in the Acquisition of Tense-Aspect Morphology

Volume 2
Issue 2
Ping Li, Sarah Maher, Erica Newmark, & Jennifer Hurley
This study investigates the role of parental input in the acquisition of tense-aspect morphology. We report statistical analyses of the distributions of tense-aspect morphology with different verbs in parental input to children between ages 2;0 to 4;0. A total of 3,505 verb tokens from the English corpora of the CHILDES database were included in our analyses. All the verbs that occur with the tense-aspect morphemes ing, -ed, and s were classified according to the four lexical aspect categories of Vandeler (1957). The frequency of occurrence of each verb type with each morpheme was computed to identify the distributional properties of tense-aspect morphology with verb semantics in parental speech. The analyses show that there is a strong association between lexical aspect of verbs and grammatical aspect of morphemes in parental aspect, and more important, characteristics of the parental input changes over time, reflecting that the associations become weaker as the child grows older. These characteristics mirror the developmental patterns in children's speech as reported in the literature. Our results provide strong evidence for the argument that the undergeneralization patterns in children's use of tense-aspect morphology stems from children' extraction of prototypical associations in the parental speech. Implications of the results are discussed in terms of probabilistic learning mechanisms that are sensitive to the statistical properties of the input.