over carefully, shakes it to see if it makes any noise, puts it in the mouth, and turns it over and over in the hands. It seems that the baby uses all of the senses to discover all there is to know about the toy. Look at a young child. Look at how the child is concentrating; the child stares intently and grasps the blocks carefully. We may assume from this observation that the child is listening closely, with the mouth open and
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