Man has a big brain.He can think,learn and speak.Scientists

Man has a big brain.He can think,learn and speak.Scientists once thought that man is different from animals because he can think and learn.They know now that animals can learn—dogs,rats,birds can learn.So scientists are beginning to understand that man is different from animals because he can speak.Animals can’t speak.They make noises when they are afraid, or angry,or unhappy.Apes understand something more quickly than human,one or two have learned a few words.Bust they are still different from us.They can’t join words and make sentences.They can’t think like us because they have no language.They can never think about the past or the future.Language is a wonderful thing.Man has been able to build a modern world because he has language.Every chid can speak his own language very well when he is four or five--- but no animals learns to sprak.How chidren learn?Scientists do not know.What happens when they speak?Scientists do not know.But scientists do know that man can speak because he has a big brain.这篇阅读的判断