题目内容：

阅读短文，从方框中选择适当的单词填空。

themselves      lions      sad      in      food

Many people may think that animals in the zoo are happy and lucky, but most of them are1.__________. Do you know why?  Animals like tigers, 2.____________ and bears usually live in forests or mountains. They run, jump, play with their children and find small animals for3.____________. But now they have to stay in small rooms 4.____________ the zoo. They don’t have to find food by 5. ____________ because the zookeepers feed them.