精选优质文档-倾情为你奉上n 掌握NE5000E/80E/40E产品的体系结构n 掌握NE5000E/80E/40E的单板构成n 掌握NE5000E/80E/40E换板操作n 了解NE5000E/80E/40E升级操作大学英语 B机考完型填空题Modern zoos are very different from zoos that were built fifty years 46 . At that time, zoos were places 47 people could go to see animals from many parts of the world. The animals lived in cages that were made 48 concrete with iron bars, cages that were easy to keep clean. 49 for the animals, the cages were small and impossible to hid
