Comparison, basic-level categories, and the teaching of adjectives.

We tested 24 caregivers of preschool children to determine whether their strategies for teaching novel adjectives are consistent with children's demonstrated abilities to learn these words (e.g., Waxman & Klibanoff, 2000). On each of four trials, caregivers had to select one of two cards, both of which showed a familiar object bearing an unfamiliar property. On the within-basic card, the object was accompanied by a second object from the same basic-level category; on the across-basic card, this second object came from a different basic-level category. Caregivers' task was to choose the card that would be more helpful to teach a novel adjective for the unfamiliar property. If the second object differed from the first in terms of a novel target property, caregivers (N = 12) stated a strong preference for the within-basic card. If the two objects agreed in terms of the novel property, caregivers (N = 12) indicated a clear preference for the across-basic card. The findings offer new insight into the speed and efficiency of lexical development, by revealing that word teachers, like word learners (cf. Waxman & Klibanoff, 2000), are sensitive to the conditions under which certain contrasts (in property or in basic-level category) are effective in promoting the successful acquisition of novel adjectives.