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Nowadays, it’s common to keep dogs as pets. We can often see dogs’ owners taking them for a walk. But have you h  of taking penguins for a walk? Here i   a piece of news from Japan. In Tokyo Zoo, penguins go out for a walk in line every day. It is said that this can make them happy and stop them from being homesick(想家的).The penguins in the zoo didn’t eat as
w  as they did in South Pole(南极) and they were u  to the keepers when they first got to the zoo, maybe they were not used to the life in the zoo. So the zoo keepers c   up with this good idea. They just let them walk as they did in South Pole. Now, all these penguins have become happy.