So there’s been some talk in the area of Humans Being Weird about human languages and how they’re bizarre and hard to learn and there’s like a million of them.
Well, one of the reasons languages are weird is because they change all the goddamn time. And I’m not talking huge linguistic changes like the Great Vowel Shift, where everyone in Southern England started pronouncing long vowels differently for no apparent reason. I’m talking "cool” meaning “sophisticated” in the 1920s, meaning “singular/unique” in the 1960s, and meaning everything from “fashionable” to “attractive” to “impressive” now - while also continuing to mean “below average temperature.” I’m talking slang.
A lot of the time, we talk about language developing and changing slowly over time - like the Great Vowel Shift, which happened over the course of 300-600 years. But slang doesn’t develop slowly - it’s not even generational most of the time. Five years ago, “dank” meant musty and cold, now it means “of high quality.” In another five years it might mean “flavorful” or “glamorous.”
One of the hardest things for non-native human speakers of another language is slang, colloquialisms, and idioms. That difficulty would have to be multiplied for an alien without even a basic context for how human language works.
What if there are species without even the concept of slang? What if they only have the one word for the one thing, with no differentiation? It would probably mean that it would take them a while to learn multiple words for the same thing; long enough that by the time they’ve mastered the use of the word “street,” it means something completely different than what they’d initially been taught.
And you know what that means?
It means that all aliens would be your dad trying to sound cool.