Japanese irregular verbs: Why suru and kuru are different

Eli: You know, Miles, I was looking at my Japanese notes this morning and I started wondering—why is it that in a language so famous for its logical, predictable verb patterns, we’re suddenly hit with these "rebels" like suru and kuru? It feels like they’re just there to trip us up, doesn't it?

Miles: It’s a great question. Most people assume Japanese is this perfectly rigid system of u-verbs and ru-verbs, but then these two show up and play by their own rules. But what if they aren't just random mistakes? What if their "irregularity" is actually a clue to how much we use them?

Eli: Right, like they're so common they've worn down their own edges over time? I mean, suru is everywhere, especially when you start attaching it to nouns like benkyou to make "study."

Miles: Exactly. They are the only two truly irregular verbs in the whole language. Let’s explore how these two powerhouses actually work and why mastering them is the real secret to unlocking daily conversation.

Eli: It’s so wild to think about, Miles—just two verbs standing outside the entire system. In a language with thousands of words, how did only suru and kuru manage to stay so... rebellious? Is it just because we say them so much that they refused to conform to the regular u and ru patterns?

Miles: That’s a huge part of it, Eli. Think about it—suru means "to do" and kuru means "to come." You can’t get through a single breakfast in Tokyo without needing at least one of those. Historically, when words are used that frequently, they tend to resist the "smoothing out" process that happens to other verbs. It’s like a path in a forest—if everyone walks the same weird, winding shortcut, that path stays exactly as it is, even if the park rangers try to build a straight paved sidewalk right next to it.

Eli: I love that analogy. So, the "winding path" of suru and kuru is just too well-trodden to change. But for a learner, that path feels like a maze. I mean, let’s look at the polite forms first because that’s where most of us start. Suru becomes shimasu and kuru becomes kimasu. That doesn't seem too bad at first glance, right?

Miles: On the surface, sure. But look closer at kuru. This is where the real mystery begins. In its dictionary form, it’s kuru. But when it gets polite, the "ku" sound completely vanishes and turns into "ki" for kimasu. And then, if you want to say "I don't come," it’s konai. We’ve got ku, ki, and ko all coming from the same verb! Why on earth does the vowel keep jumping around like that?

Eli: Wait, you’re right! Kuru, kimasu, konai—it’s like the verb is playing musical chairs with the entire "K" row of the hiragana chart. If it were a regular u-verb, like kaku for "to write," it would stay much more consistent. Kaku becomes kakimasu and kakanai. The "ka" stays as the anchor. But kuru is just... floating.

Miles: Exactly. It’s actually categorized as a ka-gyou henge or "K-column irregular" because it’s the only verb that behaves this way. And suru is its partner in crime, the sa-gyou henge. Instead of sticking to one "step," it shifts its base. For suru, the polite form is shimasu, the negative is shinai, but the volitional—the "let’s do it" form—is shiyou.

Eli: It’s almost like they’re trying to be ichidan or "one-step" verbs, but they keep forgetting their lines. You mentioned earlier that suru is a "universal verb." I see it everywhere. I mean, you can basically take any noun that sounds like an action—like soccer or cooking—and just slap suru on the end to turn it into a verb, right?

Miles: Absolutely. That’s its superpower. In linguistics, we call this "productivity." Suru is the most productive verb in Japanese because it’s the bridge between nouns and actions. You have benkyou, which is "study" as a concept. Add suru, and boom—benkyou suru, "to study." It works for loanwords too. Copy suru, click suru. It’s the ultimate Swiss Army knife.

Eli: So, if I master the conjugations for suru, I’m actually mastering hundreds of other verbs at the same time? That makes the "rebel" status feel a lot more worth the effort. But I’m still stuck on the "why." Why did these two specifically end up as the lone outliers? Was there ever a third irregular verb that eventually gave in and became "normal"?

Miles: It’s funny you ask that. Some verbs like iku, "to go," have tiny little "hiccups" in their past tense—like itte instead of what you’d expect—but they still follow the general u-verb rules. Suru and kuru are unique because their very stems—the "heart" of the word—are what change. It really comes down to their ancient origins. They’ve been central to the language since the Old Japanese period, over a thousand years ago. They are the foundation stones. Everything else was built around them, so they never had to fit into the newer "regular" boxes.

Eli: That’s fascinating. It’s like they’re the grandfathers of the language, and everyone else has to follow the new rules, but the grandfathers get to do whatever they want. But as a learner, I’m looking at these ko, ki, ku changes and thinking—how do I actually internalize this so I don't have to pause for five seconds every time I want to say "I can't come"?

Miles: That’s the "potential form" hurdle, and it’s a big one. For kuru, "can come" is korareru. Notice we’re back to the "ko" sound from the negative konai! It’s like a puzzle where the pieces only fit if you know the secret code. And for suru, it’s even wilder. The potential form of suru isn't even a conjugation of suru—it’s a completely different word: dekiru.

Eli: Wait, dekiru is just the potential form of suru? I always learned it as its own separate verb meaning "to be able to." You’re telling me they’re fundamentally linked?

Miles: They are! Historically, dekiru comes from deru, "to come out" or "to appear," and it evolved to mean that an action has the "capacity" to happen. So when you say "I can do it," you’re using a word that once meant "it comes forth." It’s a total replacement. It’s as if in English, the past tense of "to go" isn't "goed," it’s "went"—which actually comes from a different verb, "to wend."

Eli: My mind is officially blown. So suru is so irregular that it just gives up and borrows a neighbor’s house when it wants to express ability. This explains why Japanese feels so "logical" until you hit these specific points. It’s not that it’s illogical; it’s that it’s historical.

Miles: So, Eli, now that we’ve seen how suru and kuru change their shape, there’s another "rebel" move they make that trips up almost every student. It’s not just about the verb—it’s about the whole sentence structure. Specifically, that little particle ga.

Eli: Oh, I know exactly what you’re talking about. Usually, if I’m doing something, I use o to mark the object, right? Like nihongo o benkyou suru—"I study Japanese." Japanese is the thing I’m "doing" the study to. But as soon as we switch to the potential form, dekiru, everything flips.

Miles: Exactly. You don't say nihongo o dekiru. You say nihongo ga dekiru. And for a lot of English speakers, that feels like saying "Japanese is able to do," which sounds like the language itself has gained sentience and is currently taking a math test.

Eli: Right! It’s so counterintuitive. Why does the "can do" form demand ga instead of o? Is dekiru not actually a transitive verb?

Miles: You’ve hit the nail on the head. Dekiru functions more like a state or a condition than a direct action. When you use suru, you are the agent—you’re actively "doing" the homework. But when you use dekiru, you’re describing a reality where the homework is possible for you. The focus shifts from your "action" to the "existence of the ability."

Eli: So, ga is highlighting the thing that is possible. It’s like saying, "As for me, Japanese-ability exists." That’s a very different way of looking at the world than "I can do Japanese."

Miles: It really is. And this isn't just a quirk of dekiru. It’s a rule for the potential form of almost all verbs. If you can eat something, it’s ringo ga taberareru. But because suru is so common, and its potential form dekiru is so ubiquitous, this is where learners feel the friction first. It’s a fundamental shift in how Japanese handles "ability." It’s less about you exerting power over an object and more about the object being "amenable" to your skill.

Eli: That’s a really beautiful way to put it—the object is "amenable." It makes the language feel much less aggressive, somehow. But it’s a tough habit to break. I still find myself saying nihongo o... and then catching myself. Does it sound really wrong to a native speaker if I use o with dekiru?

Miles: It sounds "off," like a gear grinding. However, there’s an interesting trend in modern Japanese—especially among younger speakers—where o is starting to creep into potential forms. There’s a study that mentions this "nominative-to-accusative shift." People are starting to use o more because it reduces the "processing load." If you’re used to marking objects with o, your brain wants to keep doing it, even in the potential form.

Eli: So the "rebels" are actually leading a second rebellion? First they refuse to conjugate normally, and now they’re changing the rules for particles?

Miles: Language is never static, Eli. But for now, if you’re taking a test or want to sound "correct," ga is your best friend with dekiru. And it’s not just dekiru. Think about kuru in the potential form—korareru. Since kuru means "to come," it doesn't usually take an object anyway, but it often takes a destination. Paatii ni korareru?—"Can you come to the party?" Here, the potential is more about your schedule or the circumstances.

Eli: That’s a good point. Korareru feels like it’s asking about my "situational possibility." It’s not that I’ve forgotten how to walk to the party; it’s that my boss might make me work late.

Miles: Exactly. And that’s a nuance of the potential form we often overlook. It’s not just "do I have the skill?" It’s "is this feasible?" If I ask you shukudai ga dekiru?, I might be asking if you’re smart enough to do the math, or I might be asking if you have enough time before the deadline.

Eli: So dekiru covers both "skill" and "feasibility." That’s a lot of weight for one little irregular verb to carry. It makes me wonder about the negative side too. Dekinai is "cannot do." Does it also use ga?

Miles: Yes, absolutely. Nihongo ga dekinai—"I can't do Japanese." It’s the same logic. The "ability" doesn't exist. It’s interesting how dekiru is often written in hiragana, even though there’s a kanji for it. In modern Japanese, writing it in hiragana makes it feel more like a functional piece of grammar and less like a heavy, concrete verb.

Eli: I’ve noticed that! It feels "lighter" on the page. But wait, I’ve seen dekiru used in other ways too. Like, "Dinner is ready" is yuushoku ga dekita. That’s not about ability, is it?

Miles: Ah, you’ve found the "completion" trap! Dekiru has a second life. It also means "to be completed" or "to be made." So dekita! is what you shout when you finish your masterpiece. It’s still linked to that idea of something "coming forth" or appearing. The dinner has "appeared" on the table.

Eli: So suru is the action of making, and dekiru is the state of it being possible or finished. It’s like two sides of the same coin. One is the "doing," and the other is the "result" or "capacity."

Miles: Precisely. And that’s why you can’t just treat them as separate vocabulary words. If you don't understand that dekiru is the potential-partner of suru, you miss the underlying logic of the whole language. You’d just be memorizing random words instead of seeing the system.

Eli: Miles, I want to go deeper into something you mentioned—the suffix -(r)are-. I keep seeing it pop up in the potential form, but I also see it in passive sentences. For kuru, the potential is korareru. But isn't that also the passive form? "To be come to"? That sounds like a horror movie title.

Miles: It does sound spooky, doesn't it? This is where Japanese linguistics gets really "Inception"-level deep. The suffix -(r)are- is actually a multi-tool. It’s used for potential, passive, honorifics, and what we call "spontaneity."

Eli: "Spontaneity"? Like, something just happens out of nowhere?

Miles: Exactly. There’s a fascinating study by Ayako Shiba that looks at how this suffix evolved in Old Japanese. Originally, it wasn't about being "able" to do something or having something "done" to you. It was about things happening "spontaneously"—things that just occur without anyone specifically deciding to make them happen.

Eli: Wait, so "I can do it" and "it was done to me" both come from the same root of "it just happened"? How does that work?

Miles: Think about the potential form korareru. If you say you "can come," you’re saying the circumstances allow for your arrival. It’s almost as if your arrival is a spontaneous event that the world is permitting. Shiba argues that in Japanese, the focus has historically been on "human-centered changes." Instead of seeing a passive action as something "done" by an agent, it’s seen as a situation affecting a person.

Eli: So it’s less "The ball was kicked by me" and more "The situation of the ball-being-kicked occurred and it affects me"? That’s a huge shift in perspective.

Miles: It really is. In Indo-European languages like English, we tend to focus on the "agent"—who did what. But Shiba points out that in Japanese, even when the subject is inanimate, like a rock or a building, the sentence often includes a "human topic." The language is built around how these events impact people. This is why the potential, passive, and honorific forms all share that -(r)are- suffix. They all describe a state of being that isn't entirely under the subject’s direct, volitional control.

Eli: So, when I use the potential form of an irregular verb, like korareru, I’m tapping into this ancient idea of "non-volitional" events? I’m saying, "The event of my coming is something that can spontaneously happen"?

Miles: Exactly. And that’s why suru and kuru are so important. They are the most common verbs we use to describe these shifts. Now, remember how we said suru’s potential form is dekiru? Dekiru itself doesn't use the -(r)are- suffix because it’s so old it has its own special word. But kuru stays "regularly irregular" by using korareru.

Eli: But then there’s the "ra-nuki" thing. I hear people say koreru all the time instead of korareru. Is that just them being lazy?

Miles: It’s often called "lazy" by traditionalists, but linguists see it as a natural evolution. People are dropping the ra to distinguish the potential form from the passive form. If I say korareru, am I saying "I can come" (potential) or "I was come to" (passive)? By saying koreru, I’m making it clear: "I’m talking about my ability, not some weird passive event."

Eli: That actually makes so much sense! It’s like the language is trying to fix its own ambiguity. If the "rebel" verbs are too confusing because they have too many meanings, the speakers just start carving out new paths.

Miles: Exactly. But you have to be careful. Koreru is very common in casual speech, but if you’re in a job interview or writing a formal email, you better stick to the standard korareru. Japanese society still values that traditional structure, especially in formal settings.

Eli: It’s a lot to balance. But I’m starting to see a pattern here. All these "irregularities" aren't just mistakes; they’re echoes of how Japanese people have perceived the world for centuries. It’s a world where actions aren't always "done" by people, but sometimes just "arise" from the situation.

Miles: You’ve hit on something profound there. Shiba’s research shows that over 70% of these "intransitive" constructions in Old Japanese involve human topics. The language is deeply concerned with the human experience of change. Whether you’re "doing" (suru) or "coming" (kuru), or finding that something "can be done" (dekiru), you’re part of a narrative of events unfolding.

Eli: It makes me feel less like I’m studying a textbook and more like I’m learning a different way to exist. But let’s get practical for a second. We’ve talked about suru and kuru, but what about those "compound" verbs? You know, the ones where a noun gets married to suru? Do they follow the exact same rules?

Miles: Every single one of them. Benkyou suru becomes benkyou dekiru. Souji suru (to clean) becomes souji dekiru. If you know how to conjugate the "rebel" at the end, you can control the whole army. It’s incredibly efficient once you get over the initial shock of the irregularity.

Eli: So if I want to say "I can’t study," it’s benkyou ga dekinai. Again with the ga! It’s all coming together. The noun plus ga plus the potential form of the irregular verb.

Miles: You’re a pro already, Eli. But wait until we talk about the "passive" side of suru. It doesn't use dekiru for passive. It uses another form entirely: sareru.

Eli: Oh man, another one? Sareru? It sounds like suru but... different. Is that related to the -(r)are- suffix too?

Miles: It is! Sareru is the shortened, fused version of suru plus -(r)are-. It’s used to say things like "I was surprised" (odorakasareta) or "It is said that..." (iwarete iru—though that’s from iu). For suru compounds, it’s how you express being "affected" by an action.

Eli: So, suru is the "king" of the castle, but it has a whole cabinet of different forms for different moods. Shimasu for when he’s being polite, dekiru for when he’s feeling capable, and sareru for when things are happening to him.

Miles: And shiyou for when he’s feeling motivated! "Let’s do it!" The volitional form. It’s a busy life for an irregular verb.

Eli: Okay Miles, let’s talk about a real-world situation that always stresses me out. I want to invite someone to a party, or maybe ask if they’re available for a meeting. In English, I’d just say, "Can you come tomorrow?" But in Japanese, I have to choose between kimasu ka? and koraremasu ka?. Which one is right?

Miles: This is a classic dilemma. If you say ashita kimasu ka?, you’re asking, "Are you coming tomorrow?" It’s a question about their plan or their will. But if you say ashita koraremasu ka?, you’re using the potential form. You’re asking, "Is it possible for you to come?"

Eli: And that feels more polite, doesn't it? Like I’m not assuming they want to come, I’m just asking if their schedule allows it?

Miles: Exactly. Using the potential form korareru—or the even more formal koraremasu—is a way of being "soft." It acknowledges that the other person might be busy. It moves the focus away from their "will" and toward their "circumstances." It’s that human-centered "spontaneity" we were talking about earlier. You’re asking if the "event of their arrival" can happen.

Eli: That’s so subtle! So, by using the potential form of an irregular verb, I’m actually being more culturally sensitive? I’m not just being grammatically complex; I’m being polite.

Miles: Precisely. In Japanese, directness can sometimes feel a bit pushy. By asking about "possibility," you’re giving the other person an easy "out." If they say dekinai or korarenai, they aren't saying "I don't want to," they’re saying "The situation doesn't allow it." It saves face for everyone.

Eli: I love that. It’s like the grammar is a buffer. But what about the "casual" version of that? If I’m talking to a friend, do I say koreru? instead of korareru?

Miles: Definitely. Ashita koreru? is the standard way to ask a friend if they can make it. It’s short, it’s punchy, and it’s very clear. But here’s a tip—even in casual speech, you’ll hear dekiru used as a general "is it possible?" question. Like, if you’re both trying to fix a broken bike, you might just look at each other and ask, dekiru?—"Can it be done?"

Eli: Oh, so dekiru can just stand alone? I don't even need a subject?

Miles: Yep. It’s very contextual. Dekiru? "Can you (do it)?" Dekita! "I (finished) it!" Dekinai... "It’s impossible (for me)." It’s a one-word conversation starter.

Eli: That’s incredibly useful. But let’s go back to the "coming" part. I’ve heard another verb for "to come" that sounds way more complicated—irassharu. Does that replace kuru?

Miles: Irassharu is the "honorific" version. It’s what you use for someone of much higher status, like a boss or a customer. And here’s the kicker—irassharu can also mean "to go" or "to be." It’s like the ultimate "V.I.P." verb. But for most of us, mastering the irregular forms of kuru is the first priority. You need to know kuru, konai, kimasu, kita, and korareru before you start worrying about the super-polite stuff.

Eli: That’s a relief. One step at a time. So, if I’m at a restaurant and I want to ask if they have an English menu, I’d use dekiru, right? Eigo no menyuu, dekimasu ka?

Miles: You got it! That’s exactly how you’d use it. You’re asking if an English menu "is possible" or "is available." It’s not about the menu having the "skill" to speak English; it’s about the "feasibility" of the restaurant providing it.

Eli: And if they say dekimasen, I shouldn't take it personally. It’s just that the state of "English-menu-availability" doesn't exist there.

Miles: Exactly. You’re thinking in Japanese now! It’s all about these states and transitions. And suru is the engine that drives those transitions. Whether it’s souji suru (cleaning) or yoyaku suru (making a reservation), you’re taking a static noun and giving it a heartbeat.

Eli: It’s a lot more dynamic than I thought. I used to think suru was just a boring "helper" verb, but it’s actually the most active player on the field. It’s the one that makes everything happen.

Miles: It really is. And because it’s so central, it gets to be a rebel. It’s like the lead singer of a band—it doesn't have to follow the same dress code as the drummer or the bassist. It’s allowed to have its own unique style because without it, there’s no show.

Eli: So Miles, we’ve covered the basics of "doing" and "coming," but I feel like suru has some secret identities we haven't unmasked yet. I was reading a manga the other day, and someone said something like zutu ga suru for "I have a headache." Wait, headache is the object... but they didn't use o! And they used suru instead of "have." What’s going on there?

Miles: Ah, you’ve discovered the "sensory" side of suru! This is one of my favorite quirks. In Japanese, we don't just "have" a headache or "smell" a fragrance. We use suru to describe sensations that "arise" from the body or the environment. Zutu ga suru literally means something like "A headache is doing itself" or "A headache is manifesting."

Eli: "Manifesting"? That sounds like something out of a supernatural thriller. So my headache is an event that is "doing"?

Miles: Exactly. It’s that "spontaneity" again. You didn't do the headache; the headache is just... happening. You use it for smells too—ii nioi ga suru (a good smell is "doing"), or sounds—oto ga suru (a sound is "doing"). It’s for things you perceive through your senses that you don't have control over.

Eli: That is so different from English. In English, "I hear a sound" makes me the subject. I am the one doing the hearing. But in Japanese, the sound is the one "doing" the manifesting, and I’m just the witness?

Miles: Spot on. It’s a much more humble way of describing the world. You’re not the center of the universe; you’re just a participant in a world where things are constantly "doing." This is why suru is irregular—it’s not just a verb; it’s a fundamental building block of how the Japanese perceive reality. It covers everything from "studying" to "smelling a rose" to "having a fever."

Eli: Wow. So suru isn't just "to do" in the sense of "to perform an action." It’s "to manifest" or "to occur." No wonder it refuses to be a regular verb! It’s too busy being a philosophical concept.

Miles: It really is. And that’s why you see it in descriptions of people too. If you want to say someone is wearing a specific expression, you might use suru. Or even better, when you talk about someone’s "character." Kare wa majime na kao o shite iru—"He is doing a serious face." It’s not that he’s making the face on purpose; it’s just the state his face is in right now.

Eli: "Doing a face." I love that. It makes everyone sound like an actor in a play. So if I want to say "He has blue eyes," would I use suru too?

Miles: You actually would! Aoi me o shite iru. "He is doing blue eyes." Again, it’s not an action he’s performing; it’s a physical trait that is "manifesting." This is where suru really shows its versatility. It’s the bridge between a noun (blue eyes) and a state of being.

Eli: Okay, so let me see if I’ve got this. Suru is for: 1. Actions you do (like studying), 2. Sensations you feel (like a headache), and 3. Physical traits you have (like eye color). And in almost all those cases, it’s about something "arising" or "manifesting."

Miles: You’ve got it. And because it’s so versatile, its potential form dekiru also picks up these nuances. You can’t "can-do" a headache, obviously, but you can have a new building "manifest" in your neighborhood—atarashii biru ga dekita. "A new building was completed/manifested."

Eli: It all circles back to that "coming forth" idea. This makes the "irregularity" feel so much more intentional. It’s like the language designed these two verbs to be the flexible joints that let everything else move.

Miles: That’s a great way to put it—the flexible joints. And just like joints, they can get a bit "creaky" if you don't use them right. One common mistake is overusing koto ga dekiru because it’s "regular" and easy to remember. You know, taking any verb, adding koto, and then slapping ga dekiru on the end.

Eli: Oh, I do that all the time! It’s my safety net. "I can swim" is oyogu koto ga dekiru. It feels safe because I don't have to remember if oyogu is a godan or ichidan verb or whatever.

Miles: It’s a great safety net, and it’s perfectly grammatical. But native speakers will often prefer the direct potential form because it’s more concise. Oyogeru sounds more natural than oyogu koto ga dekiru in daily conversation. Koto ga dekiru can sound a bit stiff, like you’re reading from a manual.

Eli: So, by braving the "rebel" conjugations and using oyogeru or korareru, I’m actually sounding more "alive"?

Miles: Exactly. You’re moving away from the "manual" and into the "flow." And the same goes for suru compounds. Instead of benkyou suru koto ga dekiru, just say benkyou dekiru. It’s shorter, it’s faster, and it shows you’ve mastered the "heartbeat" of the language.

Eli: It’s like the difference between saying "I have the capability of performing the act of studying" and just saying "I can study."

Miles: Exactly! One is a legal document; the other is a conversation. And since our goal is to demystify these "rebels," the best way to do that is to start treating them like friends rather than obstacles. They’re here to help you express yourself in the most efficient way possible.

Eli: Miles, we touched on this earlier, but I want to dive back into the "ra-nuki" thing—dropping the ra in potential forms like koreru instead of korareru. Is this really the future of the language? Because my textbook has a big red "X" over it, but I hear it in every anime I watch!

Miles: It’s a classic battle between "prescriptive" grammar—what the books say is right—and "descriptive" grammar—how people actually talk. Linguistically, "ra-nuki" is a very logical change. Japanese verbs are trying to solve a problem. In ichidan verbs and the irregular kuru, the potential and passive forms are identical.

Eli: Right, taberareru could mean "I can eat" or "I was eaten." That’s a pretty important distinction to make at a dinner party!

Miles: Exactly! You don't want to accidentally tell your host that you were the main course. So, speakers started dropping the ra for the potential form—tabereru means "can eat," while taberareru stays as the passive "be eaten." It’s a way of creating clarity. And for kuru, it’s the same. Koreru is "can come," and korareru is... well, the passive or honorific form.

Eli: So if I say ashita koreru? to a friend, I’m actually being more precise than the textbook?

Miles: In a way, yes! You’re participating in a linguistic shift that has been happening for decades. Now, the "official" stance in Japan is still that "ra-nuki" is incorrect. If you’re taking the JLPT (Japanese Language Proficiency Test), you better use that ra. But in the real world? It’s everywhere.

Eli: It’s fascinating that even a "rigid" language like Japanese is constantly evolving. It makes the "irregular" verbs feel even more alive. They’re the front lines of this change.

Miles: They really are. And it’s not just about dropping sounds. It’s about how we use these verbs to navigate social spaces. Think about the "volitional" form again—shiyou for "let’s do." If you’re in a group and someone says dou shiyou?, they aren't just asking "What shall we do?"—they’re often expressing a sense of being lost or worried. "What are we going to do now?"

Eli: Oh, I’ve heard that! Dou shiyou! It’s usually shouted when something goes wrong. So suru is even used for expressing panic?

Miles: It’s the ultimate "event" verb. When things are happening, suru is there. And this brings us back to that study by Shiba on "human-centered changes." Japanese is a language that is deeply "event-oriented." Instead of a world of "actors" doing things to "objects," it’s a world of "events" affecting "people."

Eli: That explains why the passive form is so common in Japanese, even when it sounds weird in English. Like "I was rained on"—ame ni furareta. In English, we just say "It rained," but in Japanese, we use the passive of "fall" to show how the rain affected us.

Miles: Exactly! Furareta uses that same -(r)are- suffix. It’s all connected. The "irregular" verbs suru and kuru are the most common ways we talk about these events. If someone "comes" into your space and it affects you, you might use a passive or potential form to describe that interaction.

Eli: It’s like a giant web of meaning, and suru and kuru are the spiders sitting in the middle. If you pull on one thread—like the potential form—you’re actually moving the whole web of passive, honorific, and spontaneous meanings.

Miles: That’s a perfect image. And for a learner, the goal isn't to memorize the whole web at once. It’s to understand the logic of the spider. Once you realize that these verbs are all about "manifestation" and "human impact," the individual conjugations start to make sense. Konai (won't come) isn't just a random sound; it’s the "negation of the manifestation."

Eli: I’m starting to feel a lot more confident about these rebels. They’re not just trying to ruin my day; they’re trying to tell me a story about how the Japanese see the world.

Miles: They really are. And the best part is, once you master suru and kuru, you’ve unlocked a massive portion of the language. You can turn any noun into a verb, you can express ability, feasibility, sensation, and physical traits. You’ve gone from being a "visitor" in the language to actually "doing" it.

Eli: "Doing" the language. I see what you did there! Nihongo o suru.

Miles: Exactly! Or even better, Nihongo ga dekiru! "Japanese-ability has manifested!"

Eli: Miles, there’s one more area where I always stumble with these two—the past tense. For suru, it’s shita. For kuru, it’s kita. Simple enough, right? But then I see things like shite ita or shite shimatta. It feels like the past tense is never just... past.

Miles: You’ve stumbled into the world of "aspect." In Japanese, the past tense ta doesn't just mean "this happened in the past." It often means "this is in a state of completion." This is why dekita! means "It’s ready!"—it’s not just "it was able," it’s "the completion has manifested."

Eli: Okay, so shita isn't just "I did it," it’s "the doing is finished." But what about shite shimatta? I hear that a lot when people are apologetic.

Miles: That’s the "regret" or "unintentional" form. Shimau is an auxiliary verb that means "to finish," but when you pair it with the te-form of suru—making shite shimau—it adds a nuance of "I did it, and I didn't necessarily mean to" or "It ended up this way and I’m a bit bummed about it."

Eli: So if I oversleep, I say nesugite shimatta. I "ended up" oversleeping. It sounds so much more accidental than just saying "I overslept."

Miles: Exactly. And for our irregular friends, this is super common. Shite shimatta is "I ended up doing it (by mistake)." Kite shimatta is "I ended up coming (even though maybe I shouldn't have)." It’s a way of adding emotional color to these basic actions.

Eli: It’s like the "rebel" verbs are the canvas, and these auxiliary verbs are the paint. You can’t have the painting without the canvas, but the paint is what makes it interesting.

Miles: And remember that shite shimau often gets contracted in casual speech to shichau. And the past tense shite shimatta becomes shichatta. You’ll hear this constantly. Yachatta!—"I did it (messed up)!"

Eli: Shichatta... it sounds so cute for something that’s supposed to be a mistake! But it’s another one of those "winding paths" we talked about. People use it so much that they’ve worn the sounds down.

Miles: Exactly. And that’s the final secret to these irregular verbs—they are the most "human" part of the grammar. They are the words that people use when they’re in a hurry, when they’re excited, when they’re apologizing, or when they’re just trying to get through their day. They’re not academic puzzles; they’re the tools of real life.

Eli: It’s so true. I feel like I’ve been looking at these verbs through a microscope, trying to count the syllables, when I should have been looking at them as a way to connect with people.

Miles: That’s the best way to look at it. Don't worry if you mix up korareru and koreru once in a while. The fact that you’re using the potential form at all shows you’re engaging with the logic of the language. You’re asking about possibility rather than just demanding action.

Eli: So the "Practical Playbook" is really: 1. Memorize the core shifts (ko, ki, ku), 2. Embrace dekiru as your best friend for ability and completion, 3. Use ga for your particles, and 4. Don't be afraid of the "soft" potential forms to be more polite.

Miles: You’ve got the playbook perfectly. And one last tip—listen for these verbs in the wild. You’ll hear shiteru (a contraction of shite iru) everywhere. It’s the "ongoing" state. Nani shiteru no?—"What are you doing?" It’s the pulse of daily life in Japan.

Eli: Nani shiteru no? I’m going to use that one tonight! It feels so much more natural than the stiff textbook versions.

Miles: It really is. You’re moving from the "book" to the "street." And that’s where the real magic of Japanese happens.

Eli: Miles, this has been a total brain-expander. But for our listeners who are sitting there with their notebooks, let’s boil this down into some really actionable moves. If they want to conquer these "rebels" starting tomorrow, what’s the plan?

Miles: Love it. Okay, Step One: The Three Vowels of Kuru. Stop trying to force kuru to be one thing. Build a mental map: Ko is for "No" (negative konai) and "Can" (potential korareru). Ki is for "Polite" (kimasu) and "Past" (kita). And Ku is just for the "Dictionary" (kuru). If you can group them by function, the vowels stop being a mystery.

Eli: That’s brilliant. Ko for "No" and "Can." I’m writing that down. Step Two?

Miles: Step Two: Own the Suru Compounds. Remember that suru is the bridge. If you’re struggling to find a verb for something, find the noun and add suru. "To travel"? Ryokou suru. "To clean"? Souji suru. Once you have that, use dekiru to express that you can do those things. Ryokou ga dekiru—"I can travel." It’s the fastest way to expand your vocabulary by 500% in a day.

Eli: And don't forget the particle shift! Ga for dekiru. I think that’s Step Three: The Ga Habit. Every time you use the potential form of a rebel, imagine a little "ga" flag waving in your head.

Miles: Exactly. And Step Four: The "Soft" Invitation. Next time you want to ask a Japanese friend or a teacher if they can do something, use dekimasu ka? or koraremasu ka?. It’s a tiny grammatical change that makes you sound incredibly thoughtful and culturally aware. You’re acknowledging their "feasibility" rather than just their "will."

Eli: I’m definitely going to try that. It feels like a secret level of politeness I didn't know I could access. What about Step Five?

Miles: Step Five: Listen for the "Ra-Nuki" and the "Sensory Suru." When you’re watching a show or listening to a podcast, try to spot those dropped ra sounds in koreru or tabereru. And listen for when someone says oto ga suru for a sound or nioi ga suru for a smell. It will train your brain to stop seeing suru as just "to do" and start seeing it as "to manifest."

Eli: It’s like a scavenger hunt for grammar! That actually sounds fun.

Miles: It is! And the more you spot them, the more they become "normal" to you. The "irregularity" eventually fades away, and you just start feeling the rhythm. It’s like learning a song with a weird time signature—at first it’s hard to count, but once you feel the groove, you don't even think about it anymore.

Eli: I’m feeling the groove already, Miles. These rebels aren't so scary when you realize they’re just the oldest, busiest parts of the language.

Miles: They’re the foundation, Eli. And once you have a solid foundation, you can build whatever you want on top of it.

Eli: So, as we wrap things up, I’m thinking about what you said—how these verbs are like a forest path that’s stayed the same for a thousand years because it’s the most efficient route. It really changes how I look at "irregularity." It’s not a flaw; it’s a sign of life.

Miles: It really is. Language isn't a museum; it’s a living, breathing thing. Suru and kuru are irregular because they’ve been used by millions of people for over a millennium to express their needs, their dreams, and their daily lives. They’ve been shaped by the human voice.

Eli: That’s so powerful. To everyone listening, maybe the next time you hit one of these "tricky" conjugations, instead of getting frustrated, just take a second to realize you’re speaking a piece of history. You’re using the same "flexible joints" that have held the Japanese language together for generations.

Miles: And remember, the goal isn't perfection—it’s connection. If you use dekiru and korareru, you’re not just getting the grammar right; you’re tapping into a way of seeing the world where things manifest, where humans are at the center of every change, and where possibility is always worth asking about.

Eli: I love that. "Possibility is always worth asking about." That’s a great takeaway for life, not just for Japanese.

Miles: Absolutely. So, keep exploring, keep listening for those "K" row shifts, and don't be afraid to let your Japanese-ability "manifest" in its own way.

Eli: Thanks so much for diving into this with me, Miles. I feel like I’ve finally demystified the rebels.

Miles: My pleasure, Eli. It’s been a blast.

Eli: And to everyone listening, thank you for coming along on this linguistic journey with us. We hope you feel a little more confident the next time you have to conjugate suru or kuru. Take one of these ideas—maybe the "Soft Invitation" or the "Sensory Suru"—and try to spot it or use it today. It’s the best way to make it stick!

Miles: Happy learning, everyone. You’ve got this!

Eli: Thanks for listening. Reflect on what we talked about, and we'll see you in the next one—wait, I mean, we hope you enjoy your continued journey into the wonderful world of Japanese! Reflect on those irregular hearts, and keep that curiosity alive. Thanks for being here!