Unit 5 Music reading课时作业

一.完形填空

　　Modern zoos are very different from zoos built fifty years ago. At that time, zoos were places__1__people could see animals from many parts of the world. The animals lived in __2__with iron bars. The cages were easy to keep clean. __3__，for the animals, the cages were small and impossible to hide in. Although the zoo__4__took good care of them, many of the__5__did not feel comfortable, and they often became__6__．

In modern zoos, people can see animals in more__7__conditions. The animals are given more freedom in larger places__8__they can live more freely as they would in __9__．Even the appearance of zoos has changed. Trees and grass grow in the cages, and water flows__10__the places that the animals live in. There are few bars，__11__there is often a deep ditch(沟), filled with__12__，which surrounds a space where several__13__of animals live together as they would naturally. In an American zoo, the visitor can walk __14__a huge special cage that is filled with trees, some small animals and many birds. And it is large enough for all the birds to live__15__. In a zoo in New York, because of special night__16__， people can observe certain animals that are__17__only at night when most zoos are closed. Some zoos have special places for visitors to__18__animals that live in the desert or underwater. Some other zoos have special places for animals that live in