Three experiments examined preschoolers' and adults' understanding of distinctive semantic functions of adjectives and count nouns. Found that 4-year olds and adults, but not 3-year olds, who heard the adjective version (e.g., "a blue bird") were more likely than those who heard the count noun version ("a bluebird") to choose…

Examined in six experiments toddlers' use of syntactic cues to learn proper names and count nouns. Found that by 24 months, both girls and boys were significantly more likely to select a labeled object if they had heard a proper name than if they had heard a count noun. At 20 months, neither girls nor boys demonstrated this effect. (Author/KB)