人类是唯一使用语言的动物吗？

Are humans the only ___animals to use language?

我认为人类是想做有趣事情的动物。

I think humans are ___animals that want to do amusing things.

像灵长类动物这样的社会性动物，其行为复杂且被广泛研究。

The behavior of social ___animals like primates is complex and studied extensively.