Two-year-olds' productivity with verbal inflections.

Area of Science:

• Child language acquisition
• Developmental psycholinguistics
• Morphological development

Background:

• Prior studies show children can add inflections to novel words.
• Limited research exists on children's ability to drop inflections.

Purpose of the Study:

• To investigate if children aged 1;9 to 2;10 demonstrate productivity by dropping verbal inflections.
• To determine if inflectional dropping is rule-governed or phonetically motivated.

Main Methods:

• Experiment 1: Assessed children's addition and deletion of '-ed' and '-ing' inflections on nonsense words.
• Experiment 2: Examined children's deletion of '-ing' from verbs versus nouns.

Main Results:

• Children appropriately added and dropped '-ed' and '-ing' inflections in Experiment 1.
• In Experiment 2, children dropped '-ing' from verbs but not nouns, indicating rule-based usage.

Conclusions:

• Young children demonstrate appropriate and productive control over verbal inflectional morphology.
• Inflectional dropping in early development appears to be guided by grammatical rules rather than solely by ease of pronunciation.