There is a community of androids living in the ruins of Fresno after the apocalypse. They trade with the local humans for fusion batteries which they need for power. It is essential that they are able to talk to the humans for trade purposes, but there is one problem. The robots are programmed to speak only 3 languages, modern day English, modern day Spanish, and modern day French. But, the humans language eventually becomes a descendant of the modern day languages we speak today, and 500 years after the apocalypse, it’s unintelligible to anyone who speaks any modern language today. So, my question is, what plausible explanation could I give for how the robots could speak to the humans?
Hey, Talos! There must be something about your phone's browser that's getting in the way of the registration process. I seriously suggest connecting with a friend with a laptop and using it to create an account. I'm even going to suggest that you hold off more questions until you get this done. There's simply too many! Once you have an account, you can post to the SE folks and give them a list of your previous monikers and they can round it all up and stuff it into the new account.
Now, back to our regularly scheduled programming
This problem has already been solved, you just need to remind the reader of that fact.
The human mind is amazing at only a handful of things, one of which is pattern matching. We can pick a deer out of the landscape on a mountainside at 70mph while listening to Def Leppard and hear our baby crying from across a crowded room.
Machines, on the other hand, have had a harder time of it. That's because each and every human has a different "dialect" of language. Language is high-pitch to low-pitch, squeeky to growly, fast to slow ... and don't even mention our nasty habit of stressing the wrong syllable. The human mind is simply adept at overcoming most of this very easily (I still have a wee bit o' trouble with rual Scottish).
Honestly, people need to be thoroughly trained to professionally and correctly speak "modern English."
In the beginning was really bad speech synthesis.
Then came really bad voice recognition that hasn't improved much today (BTW, it was SHEER LUCK that the youtube example I found was a Scot!).
But, the technology has improved and with it the ability to recognize people's voices.
And your androids would have had to have that software, or they would have been stuck with literally every human who approached them with a different voice pattern.
Since your androids already have the ability to associate new sound patterns with existing references to come up with the correct meaning, all they need is time. With every deteriorated word they successfully map to the original language they begin to see patterns in language drift (which is what they were programmed to accomodate anyway).
And not too long after that they're speaking Portu-Greek with the best of them!
BTW, humans still have trouble with voice recognition, just to make a point.
Organic speech changes over time. If the androids were programmed to be able to track and adapt to variations in speech, which they almost certainly would be, this is a non-issue. The androids are capable of learning new slang and dialectical variations at least as fast as teenagers.
The critical thinking and decision making involved with making deals is actually considerably more complicated. I would expect it MUCH more likely the androids would succumb to charlatans and predatory exchange rates LONG before they were challenged by shifting languages.
The humans maintain an ambassador. (@Alexander)
The robots have have something to trade that the humans want. If the robots can't speak a contemporary human language some humans will learn enough robot language to get the point across. It might not need to be a whole language.
Trade doesn't require much language
Many animals with zero mutually ineligible words conduct some kind of trade with humans. Offering goods and demanding payment can be physically communicated.
If the robots are powerful enough that no humans have wiped them out for their scrap value, they might simply accost prospective trade partners, steal what they want and give what they would trade. Humans who thought it was a good deal would bring more of what was stolen and take steps to minimize friction in the exchange.
Robots are user friendly
They have a helpful user manual with pictures and demo videos. It could even include descriptions of the kinds of things they might like to trade for.
Robots are hackable.
They have a big file called strings_eng.txt on their harddrive containing everything they can say. Someone changes it so they are more clearly distinct to contemporary ears. As messages are figured out from context they can be replaced with local versions.