The document describes the stages of language development in infants from birth to 12 months. It discusses four stages: reflexes from birth to 1 month, primary circular reactions from 1-4 months, secondary circular reactions from 4-8 months, and coordination reactions from 8-12 months. During these stages, infants develop control over their bodies and an understanding of cause and effect. They also progress from involuntary reflexes to more intentional behaviors. The document also outlines characteristics of infant language development such as listening, speaking, print awareness, and book knowledge. Appropriate environments, materials, and adult interactions are described to support development at each stage.