As the modern society develops and the city expands more and more, there left less and less opportunities for human and animals to know each other. Based on this concern, the new public place, zoo, is created in recent centuries, offering a channel for human-animal communication.  

Urban people have rarely get a chance to touch the nature. Before the establishments of the zoo, many people have not seen any wild animals in their life, which are different from their pets. They can only get a concept of the wild animals in books and pictures, which are found much less attractive than the real ones later, as people finally see lions, tigers and giraffes... in the zoo. The zoo recalls parts of the original natures lying in our heart, which are connected with those beautiful wild lives.  

In spite of the positive things that the zoo brings us, there is also negative side of it as we standing on the perspective of the creatures captured in the zoo. The animal are forced to leave their home and start to live in a entire different environment, which may be unsuitable for them. Similar to human, animals do have affections. The zoo is like a man-made jail to them, which is a violation to their rights. 

Since everything has a hemisphere of advantage, and the other of disadvantage, I believe that the zoo is created on a useful purpose, and it brings the world much more joys than pains.

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