"Yes. Not as well as your vernacular and that's saying something but sure."

Summoned Heroes are bullshit.

"Well, the rest of us have to study that kind of thing, I mean, even getting the Skills for a field won't just tell you what the terms mean.  Do you know -"  He needs to remember that she has questions too.  "Uh, to answer your questions first, I can offer about 30 mana of spells before I fall over.  One mana is enough to, uh -"  Bella doesn't know any other standard units, does she.  "Push something about as hard as my hand can push on it for 5-and-three-quarters-seconds, maybe?"  He hasn't measured his own pushing strength, but it sounds about right.  "And if you got the translation of 『spirits』 you might already know more about them than my professors!  Maybe more than anybody else alive!  Do you know the whole 『Language』?  Can you just say things in 『Language』?  Can you tell me the quoted expression for, uh, uh, gravity?"  For a force that seems to just pull stuff downward all the time, it has a ridiculously long name, and nobody has ever figured out what the subexpressions mean.

"I do not know the whole 『Language』- I can understand you when you speak in it but I can't pick it apart at the boundaries of words very well, only some things stood out as individual words that could be swapped around. I have no sense of the grammar, I can't compose sentences, I don't think I could even repeat your whole spell word for word but I might be able to if I heard it a couple of times and took notes? I do not have productive vocabulary access for things like gravity. Though I, uh, do maybe know more about what gravity is from having attended science class. Is that one of the things I shouldn't go around telling people?"

"Wow.  Yeah, probably not a good thing to start yelling out on street corners.  So why is gravity?"

"I acknowledge this isn't a street corner but I'd like to know why I shouldn't yell it on a street corner before I yell it at you, for all that I have pretty much decided I'd better consider you trustworthy because the alternatives probably collapse into murder and I don't want to commit any murder. Speaking of things I could yell, is there any reason I shouldn't try casting your light spell?"

Uh.

The thought that if the Summoned Hero already understands spells, she could just repeat them back, well, that thought should have occurred to him, but it's sort of large as thoughts go.

"No," Haroun says numbly.  "No reason.  I mean you have to know what spells mean for them to work right, but you apparently know that as soon as you hear the spell, so sure, why not, haha.  You hear a spell and repeat it.  Why not?  That is a totally reasonable way for things to work.  Try this one -"

Bella hears:  "Light spirits, I offer a tenth of mana to create a flash of radiance."  It's only seven syllables, and after Haroun says it there's a flash like a photographer's bulb going off, forwards of where Haroun is sitting in the carriage's driver's seat, causing one of the horses to flicker its ears.

"Light spirits, I offer a tenth of mana to create a flash of radiance."

Flash!

...a brief lassitude assails Bella, causing her to stumble for the first time since she arrived in this world, though she quickly catches herself.

"...okay, cool, I can do magic. Is it supposed to be tiring? Is that a practice thing?"

HOLY SNARKLEROYS.

Haroun would ordinarily check at this point to see if Bella got the 『Light Magic』 Skill at Lv. 1, or maybe even higher.  But if she can already cast spells just by hearing them or reading them, he's not sure how to check!  Maybe see what she makes of the more advanced spells in his second-year 『Light Magic』 textbook -

Bella's later sentences catch up to Haroun's auditory processing.

"Tiring?  Not unless you're low on mana, and you shouldn't get low on mana from just expending a tenth.  I mean, it is a practice thing, and efficiency increases with Skill.  But the average 12-year-old apprentice has around two units of mana before they start practicing at all, just from, you know, existing for 12 years - oh.  Oh, dear."

"What happens if I overspend my mana."

Bella's universe doesn't have mana, does it.

"Nothing fatal!  You can't spend more than you have, and if you lose it all you, uh, feel very tired and sleepy and maybe have a nice nap.  Especially if there's anything else stressful going on at the time.  Like running into a Summoned Hero while you're already low on mana.  That is the sort of thing that could cause anybody to end up napping."

"I wasn't judging you for fainting, dude. If you showed up in my world and started literally casting spells all over the place I'm sure people would faint and that's without any specific reason to believe the best case scenario involves a huge crater."

"Well, uh.  We may.  We may possibly be looking at a delay on the craters thing, which, which I guess could be good short-term news from a certain point of view, but represents something of a long-term problem for... everybody."

"There aren't, like, mana shortcuts, where if I know how gravity works I can turn that into mana somehow?"

"That is an utterly fascinating idea but... I don't know how to do anything like that?  I can only think of only two people I've ever met who even might know something like that, and I'd expect you to have understandable trust issues with both of them."

"Do they have regrettable tattoos that say 'spy for the demon lord' on their foreheads or what."

"Er, one's a bit wacky and the other's a bit, er, heretical, and neither is in the next town over so it's a moot point at least for the next few days."

"Heretical."

"I don't think he'd get along with old tea guy."

"Are you here for some reason imagining that I spent many years of my childhood attending routine religious services devoted to singing the praises of old tea guy?"

"Er, no?  I didn't even know about the tea thing until you told me.  It's just that, I think the conventional opinion is that we should all be grateful to God for sending us Summoned Heroes at all, especially since God has never demanded any obvious payment from us in exchange.  Professor Nightstar seems to be of the opinion that, uh," how would Professor Nightstar put this, "sending us Summoned Heroes every century or two can't possibly be the best possible option God can take to benefit us all, assuming that God has enough power to send us Summoned Heroes in the first place, and therefore this reflects very poorly on God's intelligence, altruism, sanity, or all three.  No offense it's his opinion not mine!"

"I mean, unless he thinks it's my fault, unless he imagines that I'm old tea guy incarnate here to have an adventure for my personal amusement at the expense of the mortals, I don't see why this means I wouldn't get along with him. Like, that's just obviously true, if the god is in fact 'a god' and not 'a vending machine' - you don't have vending machines probably - anyway if he has other powers at all it'd be sort of weird if this was the best he could do, though he did mention it being expensive to talk to me so it's possible he's under some real sharp constraints that merely look like he's being an idiot."

"I think Professor Nightstar has opinions specifically about the fight between the Demon Lord and the Summoned Hero generating too much collateral damage even in the best case, and this... not being totally not the Summoned Hero's fault.  Though he's never told me what he thinks the Summoned Heroes should do any differently."

"Well, maybe he'll tell me, or maybe I'll decide not to ask him because there are apparently spies who want me dead all over the place, I am unsure as I am still adjusting."