摘要：A sample of 322 18 -month-old infants and their mothers were assessed longiudinally at 24 and 30 months. Matermnal utterances and styles of linguistic interaction were measured during a 10 minute free play session. Mothers completed a vocabulary checklist for infants. Longitudinal data were analyzed by multilevel modeling. Results indicated that vocabulary increased with age of infants and the growth rate was highly predictable by the size of vocabulary at 18 months. The growth rate was strongly influenced by maternal questioning and feedback. The effect of the matermal linguistic input was constant with age. Gender differences in size of vocabulary did not vary systematically with age..
关键词：maternal Linguistic input;amount of Linguistic input;Linguistic interaction styles;vocabulary acquisition;multilevel modeling
