根据以下材料，回答1-20题 The more parents talk to their children, the
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根据以下材料，回答1-20题
The more parents talk to their children, the faster those children's vocabularies grow and the better their intelligence develops. In 1995, Betty Hart and Todd Risley of the university of Kansas found a close 1 between the number of words a child's parents have spoken to him 2 the time he was three and his 3 success at the age of nine. At three, children born into professional families had 4 30m more words than those from a poorer background.
This observation has profound 5 for policies about babies and their parents. It suggested that sending children to "pre-school" ( 6 or kindergartens) at the age of four — a favored 7 among policymakers — comes too late to 8 for educational shortcomings at home. 9 , understanding of how children's vocabularies develop is growing.
One of the most striking 10 came from Anne Fernald, who has found that the difference 11 well before a child is three. Even at the 12 age of 18 months, when most toddlers speak only a dozen words, those from 13 families are several months behind other more favored children. 14 , Dr. Fernald thinks the differentiation starts at birth.
She 15 how quickly toddlers process language by sitting them on their mother's laps and showing them two images: a dog and a ball. A recorded voice tells the toddler to look at the ball while a camera records his 16 . This lets Dr. Fernald 17 the moment the child's gaze begins 18 towards the correct image. At 18 months, toddlers from 19 backgrounds can identify the correct object in 750 milliseconds — 200 milliseconds faster than those from poorer families; This, says Dr. Fernald, is a/an 20 difference.
