Fun fact: Cows have regional accents.

Attila Andics leads the lab where the study took place and said researchers were looking for brain regions that showed a different activity pattern for one language versus the other.

"And we found a brain region — the secondary auditory cortex, which is a higher level processing region in the auditory hierarchy — which showed a different activity pattern for the familiar language and for the unfamiliar language," Andics said.

"This activity pattern difference to the two languages suggests that dogs' brain can differentiate between these two languages. In terms of brain imaging studies, this study is the very first one which showed that a non-human species brain can discriminate between languages."

- Is your dog bilingual? A new study suggests their brains can tell languages apart

A little more:

… Mallikarjun said it would be worth investigating whether dogs could differentiate between languages in behavioral studies, too. 

"Whether they would behaviorally show a difference between Spanish and Hungarian, or whether this is something more subtle ... because often with neural studies, you can find differences that don't play out in the behavior."

Now, the dogs in the Hungarian study were trained not to move during the sessions, so the scientists could focus on the brain images and not their physical reactions.

But Andics said you should be able to try a version of this test at home, too.

"Start talking to your dog in a language they have never heard," he said. "They will probably look surprised."

Wüf!

Yes, because they communicate with natural behavior (I'm blanking on the word here. It's behavior they were simply born with)

Language is learned, but you can still "understand" another human if they are angry, crying, or laughing, no matter where they are from.

The answer is yes btw (except for trained commands)