title: What do children with specific language impairment do with multiple forms of DO?
abstract: OBJECTIVE
  This study was designed to examine the early usage patterns of multiple grammatical functions of   DO in children with and without specific language impairment (SLI). Children's use of this plurifunctional form is informative for evaluation of theoretical accounts of the deficit in SLI.
  
  
  METHODS
  Spontaneous uses of multiple functions of   DO were analyzed in language samples from 89 children: 37 children with SLI, ages 5;0-5;6 (years;months); 37 age-equivalent children; and 15 language-equivalent children, ages 2;8-4;10. Proportion correct and types of errors produced were analyzed for each function of   DO.
  
  
  RESULTS
  Children with SLI had significantly lower levels of proportion correct auxiliary   DO use compared to both control groups, with omissions of the   DO form as the primary error type. Children with SLI had near-ceiling performance on lexical   DO and elliptical   DO, similar to both control groups.
  
  
  CONCLUSIONS
  Plurifunctionality is not problematic: Children acquire each function of   DO separately. Grammatical properties of the function, rather than surface properties of the form, dictate whether children with SLI will have difficulty using the word. Overall, these results support the extended optional infinitive account of SLI and the use of auxiliary   DO omissions as part of a clinical marker for SLI.
authors: University of Kansas, Lawrence, USA. mabel@ku.edu
authors: Mabel L
authors: ML
authors: Rice
authors: Megan
authors: M
authors: Blossom
mesh_terms: D002663:Child Language; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007802:Language; D007804:Language Development; D007805:Language Development Disorders / Q000503:physiopathology*; D007807:Language Tests; D008037:Linguistics; D008297:Male; D010700:Phonetics; D013068:Speech Production Measurement