________（49）A.At three he knows about 1 000 words

________（49）

A.At three he knows about 1,000 words which he can put into sentences,and at four his language differs from that of his parents in style rather than grammar.

B.What was missing was good mothering.

C.Lots of information about benefits of baby signing and best ways to go about it can be found.

D.Insensitivity of the mother to these signals dulls the interaction because the child gets discouraged and sends out only the obvious signals.

E.If these sensitive periods are neglected,the ideal time for acquiring skills passes and they might never be learned so easily again.

F.And even more incredible is the young brain’s ability to pick out an order in language from the hubbub of sound around him,to analyze,to combine and recombine the parts of a language in novel ways.