阅读下面短文，在空白处填入适当的内容或括号内单词的正确形式。
Have you ever heard
of friendships among animals? At a zoo in Germany, an unusual friendship
developed {#blank#}1{#/blank#} 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 friendship
{#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.
