Bella instinctively understands her new language abilities about as well as human beings instinctively understood their own language abilities three thousand years before Noam Chomsky was born!  She knows nothing about etymology.  She's not sure she knows any words, really, just... uses words correctly every time she tries to think of a sentence in the new language?  She can produce rhyming sentences if she likes.  She can think of words that sound like grash (horse fodder) such as glash (dagger) and maybe if she plays around with that enough she'll be able to produce a funny pun.  She can talk like Fire Spell Guy did or talk like Stabby did, though she'd be hard-pressed to come up with any particular thoughts about the difference.  If she tries to generate a third accent, she won't be able to think of any.

The spellcasting language... she can remember some of the words Fire Spell Guy used.  Manca, offer.  Súlënár, spirit of fire.  She does not know any other words in this language.  She can't seem to imagine any new sentences in it.  She can't rearrange words she remembers Fire Spell Guy using in a new pattern that feels grammatical.

She can read and speak; can she write? Can she do things like verb nouns? She wants to go back and get her coat where she dropped it on the hill but doesn't want to leave poor Fire Spell Guy alone and unconscious. She waits and occasionally nudges him with her foot.

She can write!  She has good handwriting too!  The symbols look just like the ones on the cover of those magic books.  She knows how to verb nouns, though in this language it seems you have to verbize nouns, judging by the results.  She doesn't know what this language is called, by the way - that proposition seems to lie on the other side of some hard-to-define but surprisingly solid border between skills and memories, or maybe it's knowing the labels for concepts versus knowing facts about the world.

Foot-nudging: fails, fails, fails, works perfectly.

"Hello. You fainted. You okay?"

Haroun Pevers awakens with his foot being nudged by the Summoned Hero, who's right there and looking down at him.

There's no cultural equivalent of this experience in terms of Bella Swan's Earth.  If one tries to translate it anyways, it might go like this:  Remember how George Washington kept slaves, but also played an important role in history?  Remember how Thomas Edison treated his assistants poorly, but also played an important role in history?  Remember how Isaac Newton believed a lot of crazy stuff, but also played an important role in history?

Now imagine that George Washington, Thomas Edison, Isaac Newton, William Shakespeare, Babe Ruth, Paris Hilton, and the historical Jesus are all the same person, and that person is Cthulhu, and if you meet them personally it means a nuclear war is going to start in the next few months.

The first words out of Haroun's mouth are, "I'm sorry, I was almost out of mana - I tried casting some spells, earlier on -"

It seems to matter to him deeply that Cthulhujesus knows he wasn't just a weak little boy.

"I remember, I appreciate that you stopped trying to set me on fire, it was very gracious. I - look, I don't know your relationship to the women outside, I don't even know if my read of this whole highway robbery situation is right, I'm really sorry to have dropped in on you like this, I don't think I have made things worse for you unless you were otherwise going to toast Stabby and his friend but it's apparently a very mixed blessing if that, I apologize. That having been said where am I."

Haroun visualizes being transported to another world and asks himself what he'd like to know first.

"There's a small town called Relis further in the same direction down this road after traveling another (an expression for an uncertain duration that evaluates to 1.6-4.8 Earth hours).  We can probably still make it before nightfall.  You're in the kingdom of Relica.  The sun above us is called different things in different kingdoms but here we call it Elhom, so in our terms the planet is Elhom IV.  Elhom IV has periodically appearing Demon Lords who show up at around the same time as Heroes, and try to kill everyone in general plus you personally.  I hadn't heard about the Demon Lord before now, so if they have assassins out looking for you it's still pretty quiet.  You represent an incredible amount of bad news for a lot of powerful people who aren't in the habit of taking bad news well, or huge opportunities for anybody who wants more power than they already have.  If I were in your boots I'd try to be less visibly from-another-world while I got my bearings.  I'd offer you shelter at my family home, but it's another week's travel, and you sort of gave away all of the money we would have needed to get there.  I've got enough left for one night's hosting for us in Relis, and if you want to stick with me any further than that, one of us has to earn some money before we can go any further."

"I apologize about the money thing but at the time I was batting one out of three on orientation to person place and time so it didn't seem like a good opportunity to commit my first homicide. Do you have a loose guess about how somebody with whatever powers I'm likely to have - so far I've just noticed creepy levels of twitch with the sword and a cure for my neurological balance disorder - makes money around here?"

It's been a while since the last Summoned Hero.  As of this point, it hasn't yet occurred to Haroun that Bella is previously from a nonmagical universe, or that she wouldn't already have her own Skills.  His natural interpretation of the question is that he's meant to guess what Skills she would have, since a Summoned Hero must have too many of those for her to start listing them; and for him to guess how she can make money accordingly.  "Creepy levels of twitch" and "neurological balance disorder" didn't translate in especially helpful ways.

"There's a minor dungeon, an hour or two east of Relis, if I'm remembering correctly.  We could get you registered at the Adventurer's Guild and you could go clear it out tomorrow; that'd get you plenty of money.  Don't smash the core though, that'll cause all kinds of trouble."  Haroun glances up to estimate the position of the Sun.  He was out for... a quarter of 1.6 hours, maybe?  "Uh, should we get moving if we want to get to Relis before nightfall?  Or can you just -"  Haroun makes a vague gesture meant to imply the girl picking up the carriage and running to Relis directly.

"- can I just what? If I have the ability to teleport it's hiding. Like I said, all I've noticed is the sword thing and no longer tripping all the time."

Haroun is confused.  "What do you mean, if you have the ability to teleport it's by hiding?"  Bella is speaking fluently, but this introduces some grammatical ambiguities that aren't quite like the corresponding English ambiguities.  Haroun is imagining Bella pretending to teleport through turning invisible and sneaking around.

"I do not have introspective access to my powerset. I have tried some stuff based on incredibly scant and cryptic information from the guy who dropped me here and none of it worked. I didn't notice I could use the sword till I tried swinging it and wasn't confident about the balance issue being gone till after that. Oh, and the language thing. I can try more stuff but I do not know what literal base level actions constitute trying nor what might work."

She doesn't have introspective access to - !

"Are you saying you just got a bunch of new high-ranked Skills and you don't know how they work?"  This explains something about the size of craters left behind when Summoned Heroes fight.  "Stop trying things!"

Unfortunately, Haroun also speaks this language fluently and idiomatically.  The way in which he says "stop trying things" is by using an idiom based on a historical reference that will sound to Bella vaguely like "Darmok and Jalad at Tanagra" which carries an undertone of "don't randomly try launch codes for nuclear weapons".

"So, uh, my language power also doesn't work all that well and that sounded very urgent and I'm not clear what it meant."

"...you want to get started towards Relis while we keep talking?"

"Do you know how to drive? I've... it's not that I've literally never been this close to a horse but I don't know how to operate one, let alone one drawing a vehicle."

Haroun checks the horses.  He probably should have done that earlier.  They seem fine as far as he can tell, though.  No visible wounds.  He's not exactly a 『Tamer』.

Haroun ensconces himself in the driver's position for the carriage.  Driving wasn't his job, but he knows how to do it adequately, if not well.  Does the Summoned Hero want to ride in the carriage or stride alongside?  Striding beside will make it easier to talk.  (Obviously the Summoned Hero will have enough stamina that she could sprint all the way to Relis without getting tired.)

"I'll walk for now, might want to hop in later if my feet start hurting. Do you mind if I go get my coat, I dropped it and have no real reason to expect to need it but leaving it lying around doesn't seem great."

If George Washington was a nuclear weapon and he asked you if it was okay for him to grab his coat, would you tell him no?  Haroun neither.

"Go ahead."

She goes and gets her coat. She jogs, it's exciting and novel that she can jog now that she isn't doing it around dudes with swords. She stashes coat and backpack in the carriage but takes out her notebook so she can write while she walks, because she can probably do that here. She collects all the bodies, tries to load them into the carriage in the least bleedy way possible, for possible later looting and burial or whatever they do around here. And she falls into step beside Haroun. "So, the very urgent thing I didn't understand, what was that in minimally idiomatic terms."

"Elhom IV has a cycle.  Hunters gather and form villages, villages form towns, dungeons spawn, cities form around the older and larger dungeons, with adventurer's guilds, and mage academies once there's a source of mana potions and enough paper for books.  The Demon Lord and Summoned Hero show up.  They fight.  If the Hero is stronger, kingdoms that are far enough away will keep enough of their cities to survive.  Otherwise the cycle starts over.  I'm not sure what Skill a Summoned Hero uses when there's a mountain in her way and she feels like obliterating it instead of taking the long way around, but trying all of your new Skills in order doesn't seem like such a great idea."

"What do you mean 'in order'? How would there be an order to the things I don't have any introspective access to? Also: the dungeons spawn? Like, they just appear? And they're a natural resource and not just a weird hazard?"

It is starting to dawn on Haroun that Summoned Heroes may not just be epic adventurers from another place with more powerful monsters and skills, who get called in to clean up his own lesser dimension's dirty laundry.  Summoned Heroes may be more different than that, and come from a more different place.

Haroun considers the hints he's been getting so far, extrapolates in the same direction he's been updating so far, and tries jumping ahead.

"Don't take this the wrong way, especially if the answer is no, but were you actually some manner of weirdly-shaped monster from an utterly different and alien dimension, who just got granted human form and speech?"

"Uh, I suppose it's distantly possible that my entire sensorium is rendering the people I encounter including myself into a form I feel more comfortable with, but assuming you actually look like I'm seeing you, you appear to be a member of my species, and I think I am the same shape I was before I got here minus the lethal injuries. Two arms, two legs, two eyes, hands, that kind of thing. I've mentioned the language situation, so I guess you could say I've been granted human speech in the sense that this is human speech and I was granted it? But the phonemes in this language, whatever it's called, would have mostly been pronounceable without it, I think. Differences from my dimension that I have so far noted are that we don't have magic, enjoy a higher tech level, do not regularly even on an infrequent basis host visitors from other dimensions at least not as a matter of common knowledge, don't have a demon lord problem, uh, live on the third planet around our sun instead of the fourth..."

Don't have magic?  Enjoy a higher tech level?

Mysterious language skills have limits.  Bella's native concepts don't carve Haroun's reality at its joints.  In his conceptual universe, there are elemental Skills like 『Fire Magic』 or 『Light Magic』.  There are 『Sword』 Skills and 『Tamer』 Skills and 『Smithing』 Skills.  There's nothing that stands out to him about the difference between quenching a sword's steel to harden it, and carving runes on the hilt to strengthen it.  The concept Bella tried to convey is something like "we have no fish", meaning to say that whales and dolphins are still around, as said to somebody who's never heard of the category "mammal".  Bella can notice problems like that, but only if she slows down to mentally re-hear her own words after she's fluently spoken them; she's less likely to notice if she's distracted or already speaking her next sentence.

In this case, it comes out roughly as "we don't have rituals-or-invocations-that-trigger-Skills, and have more powerful Skills-that-produce-durable goods".

Haroun would love to hear more about all of this, though.  "Third planet from your sun?  Wouldn't that be much hotter than here?  And what do you mean, you're the same shape minus lethal injuries?  How do you subtract lethal injuries from a shape to change it?  Uh, do we mean the same thing by subtraction?  Like, nine minus three is six..."  Haroun then pauses, wondering if that's an unambiguous example of subtraction.  He thinks it is?  But maybe he should have used larger numbers with no common factors, in case he's missing some other relation between 9, 3, and 6.  It does seem clear that the Summoned Hero and him are having some communications difficulties, so he needs to be careful about that kind of thing.