精选优质文档-倾情为你奉上第四部分 完形填空（2011年12月网考）5.Modern zoos are very different from zoos that were built fifty years ago . At that time, zoos were places 1 people could go to see animals from many parts of the world. The animals lived in cages that were made 2 concrete with iron bars, cages that were easy to keep clean. Unfortunately for the animals, the cages were small and impossible to hide in. The zoo environment was anything but natural. 3 the zoo keepers took good care of
