形形色色的熊家族（补全句子）
There are many kinds of bears. Some bears live in warm places, like sun bears. Some bears live in cold places, like polar bears. Bears are different colors, too. They can be white, brown, or black. Some bears eat plants. Some bears eat animals. Bears have long noses. They have claws and fur, too. Baby bears are called cubs. When it gets cold, bears sleep in dens for the winter. Dens can be in trees or caves. When they are sleeping all winter, it is called hibernating. Bears do not eat when they are hibernating.
根据短文内容补全句子，每空限填一词。