We know that humans think using the language(s) that they speak, but what to creatures without language think in? is it possible that they don't really think at all about anything that isn't immediately in front of them. A dog for example would see food and want to eat it based on impulses generated from the smell of it and the dogs hunger. If the dog wasn't hungry it wouldn't have such a strong impulse to eat the food.

When a dog is alone and trying to sleep does it think of what it did that day? how can it do that without a language? It must just think of nothing, right? but we know how hard that is so I can't think of how they do it, what ideas do you have? Also what kind of things would be in a humans head if he/she didn't know any form of language?

The development of a language must provide so much extra mental freedom for a being, without language a being would be restricted to thinking about only a small scope of things that they have experienced before. It would be impossible to think of things like abstract math and advance reasoning. Imagine how hard it would be to play a game of chess without thinking using a language, I dare you to try it! If you're like me you will find yourself using language without noticing.

Language is also an obvious requirement for communication and hence a society. Language is the key to advancement in not only endeavors in fields such as technology or social structure but also in the development of cognitive ability.