"Hi...?" she says to the people in front of her in a rather small and confused voice.  Then, after a moment's thought, "Tsi-imbi?"

The people whose home she has appeared in look very confused. They do not seem to know what "tsi-imbi" is supposed to mean.

The one in the chair reaches down and tugs a dangling end of the restraint and it comes untied and the one on the floor catches it before it falls. Puts it in his pocket. Asks her something in Not Baseline.

"Language... difficulty?"  Welp it looks like she's in another world that doesn't speak Baseline.  Not really what Thellim was expecting from a plane crash but better than she was expecting so she should try to be cheerful and proactive about this she guesses.

They don't super seem to know what to do about her. The one on the floor haltingly tries another language.

It won't necessarily occur to Thellim yet that anybody speaks more than one language.  This looks like an equiv-tech world with artificial nice things, it no doubt speaks a carefully optimized artificial language, and universality is among the most desirable properties of such.

"Language difficulty," she repeats.  "This is a complicated sentence which demonstrates that I in fact speak a completely different language from anything you've ever heard of, implying that when I appeared I did so from very far away.  You can deduce that, right?"

The one in the chair points at himself and says, "Brian."

The one on the floor mimics the gesture. "Jackson."

Okay, good, cooperative Civilization.  Not that you could manufacture chairs and houses if people didn't have market economies, but still, good to know.  "Thellim," says she, mimicking the gesture.

They confer amongst themselves some more. Jackson pulls a rectangle out of his pocket and starts poking it; it lights up at the first poke and the lights change every time he pokes it.

What a nice higher-tech world she has found herself in.  Might have been nice to find herself in one that spoke Baseline, but maybe Baseline is just such a poorly constructed language that optimizing her experience from here on out will be helped by her learning a new language from scratch.  That's about the most optimistic spin Thellim can manage to put on current events.

She is, of course, consciously aware that this version of the story was generated by putting a maximally optimistic spin on things.

This... really was not how she was expecting her day to go, and it does not obviously conform to any of the things she thought was true about reality, or for that matter, true about stories.

Thellim waits.  Crossing language gaps is a matter for specialists, which she is not, and these two people don't seem to be that either.

"Tehillim?" attempts Jackson after a minute.

"Thellim.  Thel-lim.  Thellim.  If you have higher-tech mathematics and software that are trying to learn my language and can do that just from hearing me talk for a while, I can start babbling as best I can.  How do I convey that, though... I don't want to start babbling at you if that doesn't help at all..."

The locals murmur to each other a little more, shaking their heads occasionally.

A snatch of music starts playing from the phone. Jackson pokes it a few more times; the music stops. He says something to Brian. Brian says something back. Jackson points the rectangle at Thellim, and it flashes brightly.

Was that a cue to talk to somebody who's now watching?  Well, won't hurt if she makes a mistake about that.  She repeats the gesture, pointing at herself.  "Thellim!"  Long pause.  "Language difficulty!  Tsi-imbi!  I'm from dath ilan!  As you can see, I speak an unknown complicated syntactical language with at least some repeated words, if I go on talking long enough I ought to at least repeat a preposition or something, so unless your first theory is that somebody devised a whole new language and learned fluency in it as a prank, I probably come from another world!  Though I'd totally understand if you thought pranks were a higher prior probability than that.  I hope your world gets lots of people like me and that you do not start out with an astronomically high prior that everyone in this house is insane!"

Jackson puts the phone down during the pause. He pokes it a few more times. He holds up one finger in what is probably a meaningful gesture of some kind.

Then there is an unvoice in her BRAIN.

[Hello?]

Oh my WHAT.

"Hello?"  :How do I [ ] things?:  {Am I doing this right?}  <I bet I'm not doing this right.>

[Uh, I got most of that. I'm doing all the work, here, just naively directing thoughts at me will do.]

Should she do tsi-imbi?  No there is actually no point in going 'tsi-imbi' solely through an apparent telepathic connection it is rather a self-undermining sort of strategy.  [I'm Thellim.  I was in a crashing plane.  Now I'm here in what appears to be an entirely different world; mine had less advanced phones, and nobody who could speak inside your mind.  I hope you already have substantial experience with that kind of thing happening.  But if not, I can fluently speak, read, write, and translate a language that doesn't exist, I've memorized some poetry and famous speeches in that language, I'm wearing manufactured clothing with labels that don't correspond to any local manufacturers, and, probably hardest of all to fake, I'd be surprised and interested if my genetic markers bore any resemblance whatsoever to any local subpopulation.]

[People appearing after plane crashes is actually very weird. Uh, I don't have lie detection but I could hire someone who does if whether you are from another planet is ever importantly at issue.]

[I'll be moderately impressed if your world is covering all of its bases so well that a randomly sampled average person from another, moderately lower-tech world knows nothing very valuable or useful to your world.  But I suppose most valuable knowledge of that kind is valuable whether or not the person is telling the truth about how they got it?  It is nice not to be thought insane, though, especially when one is not insane.]

[I mean, I don't think it's urgent to figure that out definitively right this second before we know, like, where you're going to sleep tonight. Assuming on your planet people need sleep.]

[We do.  So far as I can tell by looking, people here look like the same species I am.  Ah... on my world, if somebody verifiably materialized from elsewhere, versus just saying they'd materialized from elsewhere, there would be very different responses involving, respectively, the largest university-inquisition in the history of time with an uncapped budget, or alternatively, psychiatric intervention?]

[If you want to be admitted to a psychiatric hospital staffed by people who are mostly monolingual speakers of English be my guest but it's not a popular option even for native speakers and I'm not planning to insist as long as you do not appear to be a danger to yourself or others. I am sure some kind of academic would be interested in you but I do not have one in my pocket.]

Thellim is now very confused.

[Things here are very different than they are on my world.  Do you not have... research institutions?  Collections of specialists, who are supported by venture capitalists trying to capture prizes, which prizes are funded by most of the world's public to produce public goods?  And, I mean, it wouldn't be the first thought to cross my own mind, but do you not have venture capitalists who would fly out by the thousands to meet somebody from another world?]

[We have research institutions but you seem to have a remarkably specific preconception of how they should work considering the other-planet thing. I don't have a venture capitalist in my pocket either. Do you want me to get on Twitter and post "hey, somebody I knew in school had somebody who claims she's from another planet land in their kitchen"? Because that will be taken as an experimental fiction project.]