This study investigates structural and pragmatic aspects of caregiver input in English and Korean that relate to the early development of nouns and verbs. Twenty mothers in each language were asked to interact with their one-and-a-half-year-old children in two contexts: book-reading and toy-play. Overall, English-speaking mothers use more nouns than verbs, and focus more on objects than on actions. In contrast, Korean-speaking mothers provide a balanced treatment of nouns and verbs, and focus on objects and actions to a similar degree. A significant context effect indicates that whereas English-speaking mothers emphasize nouns in both contexts, Korean-speaking mothers do so only in the Books context. In the Toys context, they provide more verbs and focus more on actions. These data suggest that systematic comparisons of caregiver input within and across different contexts provide a richer and more accurate account of the variability that can occur across languages and cultures.