As someone who studied linguistics, one of my biggest pet peeves in high fantasy is when our stalwart protagonist first encounters the elves in the forest, and he can of course speak with them because he’s half-elvish. All elves speak elvish. It’s a racial thing. Now, I’m not saying that it couldn’t be a racial thing. Sure, you could have some weird alien life form where they all have psychic powers from birth (But if they have psychic powers, do they even need a spoken language? Just sayin…) But presumably, your elves are kinda like people.
People have weird misconceptions about language. One of them is that if you learn it as a child, through total immersion, you will be fluent your whole life. So they sign their baby up for the total immersion French/Hebrew/Japanese, where the baby learns how to say “kitty” or “doggy” or “hello” for an hour of “total immersion” a week. First of all, that ain’t gonna work. An hour a week is insufficient, babies aren’t magical language sponges. (Well, they are, but mostly because they have nothing better to do with their time than sleep, poop, and learn their first language. And they are very motivated to learn. Those milky big people keep babbling at them, and it’s terribly important to please the soft, warm, food-bringers. ) Secondly, babies aren’t as dumb as you think; they’re not going to bother learning to say “doggy” in Hebrew if it’s not relevant to them in real life.
Which brings us back to our half-elf protagonist. Yeah, maybe he hung out with his elf mother when he was just a baby. That’s great! The first few months are critical for language development, in that that’s when a baby learns which phonemes are important. Babies who hear English learn that the difference between “ba” and “pa” is important, but the difference between “ta” (with the tongue behind the teeth–dental) and “ta” (with the tongue on that first ridge in the roof of your mouth–alveolar) not so much. That’s why Japanese people think that “light” and “right” sound the same: they learned as babies that the difference between “l” and “r” wasn’t important, so they started ignoring it. I bet us English speakers are sources of endless amusement when we learn Thai and mispronounce “po” (aspirated), as “po” (unaspirated). Hilarious foreigners! So our half-elf protagonist can hear the difference between “ta” (dental) and “ta” (alveolar). We’ll even make it so that his elf mommy didn’t tragically die by that orcish arrow until he was five. That means he can understand a few words, and maybe even speak a few words. He can probably understand a lot more than he can speak.
So when he’s a man, and he encounters a trio of elvish villagers, he can tell them about the band of orcish cavalry about to flank the vanguard about two miles east of the ford. Well, no. Let’s look at the vocabulary here. He stopped learning elvish at five. Would a five-year-old know “vanguard” and “flank” and “cavalry”? Here’s what he’s really saying:
“Bad horsie-man come down river place two, two (he draws a blank on the word “mile” and remembers that elves use metric) that side of wet place.”
The elvish villagers find him hilarious. When he’s out of sight, one of them imitates him for his friends, and is rewarded with snickers and laughter. They find it especially funny the way he mispronounces the alveolar “t” by putting his tongue too far forward. It sounds like he’s lisping. They have no idea what he was trying to say, because they’re clannish and insular and because foreigners so rarely learn their language, they’ve never heard Elvish spoken with a foreign accent, and they can’t understand him.
Wait a minute, you say. How could they not understand their own language? Trust me. I once met a woman from Alabama who was travelling in Germany, and she could not understand the conductor because his English was accented. Danish people, too, have told me that they can’t understand foreigners who speak Danish, because only Danes speak Danish. If the only dog you have seen is a Beagle, it takes some exposure and understanding before you also classify Chihuahuas and Great Danes as dogs. If the only people you have ever heard speak your language are your parents, then it’s going to take a while before you can understand someone from the east side, who speaks a little differently.
But all is not lost for our half-elf protagonist. First of all, you can communicate an awful lot without language. With charades and stick drawings in the mud, he convinces the villagers of the doom awaiting them. They defeat the orcs, and in gratitude, invite him to stay with them in their village. There, he triples his elvish language knowledge in a week. What? Learn a language in a week? Yes, remember? He already knew some, and now he gets to practice.
See, the thing about language is that you get better at the ones you use. And if you have a good, solid reason to learn a foreign language, you are more likely to learn one. People who trade, or otherwise deal with other cultures, especially if their own language is not widespread, are likely to learn other languages. Macedonian airline pilots learn foreign languages. Finnish tour directors learn foreign languages. American softball coaches do not. If you don’t travel, if you don’t interact with foreigners, you don’t have a compelling reason to learn another language. Wanting to learn Portuguese because you think it would be cool to impress people at parties that you knew Portuguese is not a strong motivator. Falling madly in love with a smoking-hot Brazilian exchange student who doesn’t speak English? Strong motivator.
So our half-elf protagonist freshens up his elvish language while he’s with the villagers. He learns words that are important to village life: pot, crop, river, sky, weather, wolves, cottage, doctor, etc. He’s not going to be able to learn military terms from them, or terms for magic, or mathematics, because these are simple villagers. They hardly have any books, much less the internet. But say they do. Say there’s one wise woman in the village who travelled to the elvish university, where she successfully defended her dissertation in cantrips and illusions. She has a good vocabulary, and she can teach him some abstract words when they’re chatting late by candlelight about philosophy and orcish military strategy.
After a week or two of total immersion (total immersion doesn’t mean an hour a day, it means that no one speaks to you in your own language twenty-four-seven) he’s remembered everything his mother taught him, and more. He’s ready to travel through the forest and warn the other elves about the orcish military threat. After many long and plot-filled adventures, he meets another band of elves. He quickly trots out his practiced introduction.
And they don’t understand him at all.
Here’s what else we forget about language. There are a lot of them. Lots and lots and lots and lots and lots of different languages. Even when two people theoretically speak the same language, they can have dialect differences which make them mutually unintelligible.* These days we have entire countries that speak the same language with one another, but that’s because we have libraries and printed books and the internet and television and mass media and people who travel all the time and talk to friends who live 1000 miles away. This is not the normal state of affairs. This is a result of literacy and high population density and a whole lot of other factors. Normally, people split off into groups and each group develops its own language. You can see this happening on a smaller scale when you have a boarding school, or a tightly-knit club. Don’t you develop your own shorthand for things? Slang? Imagine your high school got cut off from the rest of the world. You start to call a backpack a “slingy” and you call boys “bo bos” and when you greet each other you say “what’s the sitch?” Now imagine that all the other high schools got secluded too. Within a few generations, you’d be doing charades and drawing in the mud to warn each other about orcish invasions, because your local slang would have morphed into a dialect.
Of course, a universal language has a lot of advantages, besides just warning about orcs. Language unifies people. Common language makes trade easier too. That’s why having a lingua franca can be so valuable. With the exception of Esperanto, most lingua francas are the language of a people that dominated others, whether militarily or culturally or both. You usually need an empire to impose one, or a very strong structure, like the Roman Empire, the Holy Roman Church, or in the case of English, Western Imperialism. Are your elves noble creatures, who do not dominate other cultures in horrid Empires the way that us beastly humans do? No? No empire? No lingua franca.
Does your half-elf speak another language, one that your elf also speaks? This happens a lot in the real world. I had some Brazilian neighbors who didn’t speak English, and I didn’t speak Portuguese, so we had to communicate in Japanese. My Japanese was mediocre, and theirs was even worse, so we didn’t talk much. In real life, it’s a nuisance, but in a story, miscommunications can make for fabulous plot complications.
If your half-elf travels frequently, he’s going to pick up a few extra dialects. This may sound like he has to be really smart, but he’s gonna have a lot of extra room in his brain because he doesn’t have to memorize passwords to get into his accounts online. You might think that to learn foreign languages that he has to go to university for years and years, but that’s not how most people learn in pre-literate socieites. Most people learn foreign languages by trying, failing, struggling, being laughed at, feeling like their head is going to explode from being crammed with new words, falling asleep, dreaming about conjugations, then waking up and doing it all again. It’s not easy, but it’s possible. We humans are made for this. Talking is part of what makes us people.
What’s that? Your half-elf protagonist only speaks human and his mother’s elven dialect? Sorry, you’re stuck with a pidgin. A pidgin is when two cultures interact often enough that they develop a made up language of shared words. Think of Spanglish. Your elves resort to pidgin to communicate with one another. Your half-elf? He’s not gonna know this pidgin well, and even if he does, it’s not good for much besides trading salt for gold. A pidgin is not a good means for communication. You can’t discuss literary theory with one, you can only use it to trade or resolve small conflicts. He’s stuck. It’s back to charades and drawing in the mud.
But fortunately, that’s just in the fantasy world. In the real world, we have the universal human language, which we all speak from birth, and if we do meet an orc or an elf, it’s okay because they’ll speak the common tongue fluently, albeit with a slight accent.
* What’s the difference between a dialect and a language? A language has an army and a navy.