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Have you ever heard of friendships among animals? At a zoo in Germany, an {#blank#}1{#/blank#} (usual) friendship developed between a cat and a bear.
One day, some {#blank#}2{#/blank#} (worker) in the zoo noticed a black cat was in the bear's cage (笼子), and the two animals were enjoying {#blank#}3{#/blank#} (they) together. The bear keeper allowed the cat {#blank#}4{#/blank#} (stay) with the bear. And later, the pair and their friendship became {#blank#}5{#/blank#} hot topic at the zoo.
After several years, a new cage {#blank#}6{#/blank#} (build) for the bear. However, the cat was kept outside the cage, so it walked around {#blank#}7{#/blank#} (angry) and cried to be with the bear. Instead of {#blank#}8{#/blank#} (drive) the cat away, the bear keeper took pity on it and let it stay with the bear. The cat and the bear got closer than before. They often shared meals {#blank#}9{#/blank#} each other in the sun.
This may surprise humans {#blank#}10{#/blank#} they usually expect animals to form relationships with others of the same species (物种). However, it may be natural for animals to have their own ideas about who would make a good friend.
