Language - is a system that helps one to express thoughts and feelings by sounds and signs and form relationship with other language. Language is not always verbal, some animals communicate using sign language. It is also helps the animals to detect danger or warn other animals of the danger. Principles for combining words into meaningful sentences. It is also a combination of different sounds and collection of words.
I think that animals have language, because without language they couldn't express their feelings and emotions, communicate with other animals by movement and sounds, form relationships or protect themselves and their families.
Animals can't speak because they don't have physical ability, however animals like parrots can imitate sounds that they remember.