During Early Childhood Years by Doris Johnson Remarkable changes in physical, cognitive, linguistic, and social growth occur during the early childhood years.
Preschoolers seem to attain new milestones almost daily.
For example, in the area of oral language, some researchers found that preschoolers may learn two to four new words per day. By age three they use three and four word sentences and are beginning to tell personal narratives. By age 5 or 6, children may have a vocabulary of 8,000 to 15,000 words, can use most basic sentence structures, and can tell relatively good stories. Perceptual motor skills also increase steadily. At age three, most children can draw a circle and the rudiments of human figures, but by 5 or 6 they generally can draw a square, a triangle, intersecting lines, and figures that look like people or objects such as houses.