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Now a lot of people like to keep dogs as their pets．But do you know dogs were wild(野生的)animals long，long ago?

    The  1  wild dogs were trained by   2   in Europe about 10，000 years ago．These first“dogs”were not like  3  we have now．They may have been small wolves．These dogs often came near humans to  4  some food．Some of the young dogs were adopted(收養)by people and grew-up with them．

Humans believed the  5  were a help to them in many ways．The dogs helped them to hunt(狩獵)．They could smell and hear danger  6  people could．They helped to keep people    7  on cold night．So it was  8  to raise the dogs.

Now，there are many different kinds of dogs  9  they may look quite different from each other．Dog trainers think there are more than 400 different kinds in the world．The number keeps increasing with new kinds．

    Since those early days，humans and dogs have always been together，We should   10   them from now on because they are really our friends．

   1．A．whole     B，late       C．1ast      D．first

   2．A．wolves    B．eats       C．humans   D．students

   3．A．where     B．what      C．when     D．which

   4．A．serve      B．waste     C．make     D．steal

   5．A．cats       B．foxes      C．wolves   D．dogs

   6．A．when      B．after      C．before    D．as soon as

   7．A．cool       B．warm     C．hot       D．cold

   8．A．useful      B．useless    C．easy     D．hard

   9．A．so         B．and       C．but      D．although

   10．A．protect      B．kill       C．hurt     D．see