阅读下面短文，在空白处填入一个适当的词，或填入括号中所给单词的适当形式。 Have you ever heard of friendships among animals? At a zoo in Germany, an unusual friendship {#blank#}1{#/blank#} (develop) between a cat and a bear.
No one is quite sure how the friendship first began. 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 playing together peacefully. They were surprised {#blank#}3{#/blank#} well the small cat seemed to get along with the large bear. The bear keeper allowed the cat to stay with the bear. And later the pair and their unusual {#blank#}4{#/blank#} (become) a hot topic at the zoo.
After several years, a new cage {#blank#}5{#/blank#} (build) for the bear. However, the cat was still in the same cage, so it walked around {#blank#}6{#/blank#} (angry) and cried to be with the bear. The bear keeper finally took pity on the cat {#blank#}7{#/blank#} let it stay with the bear. The cat and the bear got {#blank#}8{#/blank#} (close) than before. They often sat together and shared meals in {#blank#}9{#/blank#}sun.
Sometimes it may be natural for animals {#blank#}10{#/blank#} (have) their own ideas about who would make a good friend. These may surprise humans, who usually expect animals to form relationships with others of the same species.
