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     Man has a big brain. He can think and s   1    languages. Scientists once thought that man isn't the same as

animalsb   2    man can think and learn. They know now that dogs, monkeys and birds can learn, too.

     They are beginning to u   3    that men are different from animals because they can speak. Animals can't speak.

They make much n   4    when they are afraid, or unhappy. Apes(猿) can learn some things more quickly than man.

One or two of them have learned a few words. But they can not join words to make s   5   . They cannot think I    6   

us because they have no language. Language is a wonderful thing. Man has been a   7    to build a modern world

because he has language. Every child can speak his own language very w   8    when he is four or five, b   9    no

animals learn to speak.

     How do children learn it? Scientists don't really know w   10    happens inside our body when we speak. They

only know that man can speak because he has a brain.

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