Effects of a cycled morphological intervention on selected suppletive BE forms

The purpose of this study was to demonstrate the efficacy of a cycled morphological intervention involving copula is, by comparison to a control group, and to examine the effectiveness of this intervention in producing change in untreated auxiliary is and am. Twenty-two preschool children, who produced copula is but no other suppletive forms of BE as targets, received six sessions of naturalistic intervention cycled over 24 weeks. Production accuracy levels for treated copula and untreated auxiliary is and am were obtained from spontaneous language samples elicited after 12 and 24 weeks of intervention. The cycled intervention resulted in significant improvement in copula is in comparison to the no-treatment control group at the 12 week sampling point; similar gains were observed for the untreated auxiliary is, but not am. After 24 weeks, however, gains in untreated am were significantly greater than for copula is, providing new data to suggest that generalization may also be observed for the suppletive am.