Nayoki hangs out nearby in the library in case she has questions, but eventually starts reading her own book. 

There is a book that has more information about extraplanar entities. It's mostly very technical magical discussion of summoning and binding spells, but it also has pictures of the construct-bodies traditionally given to these visitors. The earth-elementals tend to look like lizards; the Abyssal demons have random, bizarre body plans that are mostly way too many eyes and claws and teeth attached together in disconcerting ways. The planes aren't really made of the material-plane substances or phenomena they're named for; it's more a vague thematic resemblance, and gestures at what material-plane features the planar entities have a particular affinity for. Water elementals, for example, can sense weather and climate patterns with surprising accuracy, despite mostly not perceiving the material plane directly at all. 

That's interesting but not really what she wanted to know. The elementals are smart enough to bargain with, what are they like as individuals?

There's not a lot of information in this particular book about that, but there is some, sprinkled in amongst all the technical magic explanations. 

They vary in intelligence; some, like the vrondi air-elementals or sandaar fire-elementals, can keep their end of simple magically-binding voluntary agreements, but are probably no smarter than, say, mice. Others, like the khamsin earth-elementals or fire-elemental salamanders, can learn simple words to communicate with humans or other sentient creatures in the material plane, and a forgotten mage a long time ago taught them some of his language; it's now a universal dialect that the elementals apparently share with one another, that all the schools of magic which lean on elemental summoning now teach to their students.

The smarter elementals seem capable of recognizing individual humans, and will develop something-like-loyalty to those who treat them well and fairly, answering their summonings reliably. They don't have names but can usually be recognized by features of the construct-body that they build for themselves out of the offered mage-energies of the summoning. Some mages claim that different individuals have recognizably distinct personalities, but others say they haven't noticed that. The elementals do seem to vary in personality between the planes; earth-elementals are very reliable, albeit literal at following instructions, whereas fire-elementals are capricious and need very precise instructions or bindings in order to prevent them from getting up to various pranks along with the request they were summoned for. 

Huh. She wonders how much of this opacity is just language barrier.

The book is silent on this matter. 

"Learning anything of interest?" Nayoki asks her eventually. 

"I am wondering if there are any more peopley elementals or if the normal ones would seem more peopley if there were no language barrier."

"Huh! I have no idea. Maybe." 

"I'm not speaking a language, so it might be I could talk to them better."

"I am so curious how that works! You sound as though you are speaking out loud to me in words, not in Mindspeech or something. Is that not the case?" 

"I'm speaking out loud in words but they aren't... code words, or whatever it is you're doing, I'm just saying the words."

"- What? Language is not– That is very confusing to me. Here, language is not - objective, the way a diamond is the same diamond no matter who finds it, it is all particular words that only mean something because enough people have decided to use them that way." 

"I know that's how mortals do it but I think that's weird!"

"...I suppose it is, when you think about it. Mindspeech is partially language-independent, most people think and thus communicate mentally in words but the concepts are there, just less precise or clear when the speakers do not share a language." 

"Do I sound imprecise and unclear?"

"No! Not at all. You sound exactly as though you are speaking Valdemaran, which is the language I have been speaking with you, I know several. You also had no difficulty reading books written in particular human languages, I noticed." 

"Are they in different ones?"

"The two you read happen to both be in Rethwellani, Rethwellan is a major centre of magical scholarship and has been for many centuries. It is a different language from what I am speaking right now." 

"Huh. It's not really obvious to me, maybe I could learn to distinguish them."

"Maybe! In any case, it is a very useful capability you have, understanding any language. Especially when one accidentally ends up in an entire new world!" 

"Oh, wow, that would be really inconvenient if I landed and couldn't understand anyone!"

"It would be! We might have tried to use Mindspeech to communicate, but I imagine that would have alarmed you." 

"Yes."

Sunspring stretches. "Anyway. Want some supper? It's getting to that time."