Verb stem = Noun

About a week ago I realized that some nouns just seemed to be verbstems, which after being confirmed by seanblue, kind of blew my mind.
I had never realized this, learning vocab terms completely seperate, which seems like such a waste.

I know that this isn’t possible with every verb and sounds unnatural with others, but once I started paying attention they just seemed to be everywhere.
To name only a few from WaniKani itself.

Is this taught in beginner textbooks? Did I just skim over it while going through Genki? Am I just really slow and everyone else realizes this on their own?
It seems like such a simple thing and somehow I completely missed it.


KawaJapa CureDolly uses stems in her Organic Japanese method. ^^ I find it so much simpler. I can’t attest too much on how other learning resources do it, but I feel like this fact isn’t brought up enough in courses.


Yeah, I don’t recall it ever being mentioned in Nakama - I just noticed on my own. Couldn’t say how long it took me, so I couldn’t comment on your slowness. :stuck_out_tongue:

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If I remember correctly, it’s very briefly talked about in Mina no nihongo volume 2. But it’s very late in the learning process and I think for most classmates in my class it was also a big surprise.

The stem-as-noun also explains very neatly why the construction verb-stem に + 行く (usually taught very early) is not a super weird exception, but in the end a fairly regular nounに + 行く.


買いに is some sort of noun, “go to buying/shopping”

It also explain why it’s not mandatory that 買いに and 行きました are always sticked together. 買いに can be move in the sentence, like any nounに.

It almost never happen, but for example I remember being utterly stumped by this sentence from a graded reader :


Why 取りに can float mid-sentence like this ? Because I think actually the sentence is like this :

そして、また、魚を取りに ( 川の中に入って ) 行きました。

So it’s a 取りに行きました sentence, very literally, “And then, again, he entered into the river and went to catch fish”.


After reading this post, I started to notice in the lessons that it actually does tell us that some nouns can be verbs as well as adjectives.


I had so many “aha!” moments watching Cure Dolly that I can’t recommend it enough. The whole android conceit may take some getting used to but the learning method is probably been the most helpful to me so far.

This is one of the things that I think Cure Dolly covers really well. The fact that Japanese is so very noun centric. Verbs can become nouns. Nouns can become verbs.


Well, that’s a する verb, which not quite the same thing. Many nouns can form compound verbs by tacking する “to do” on the backside, with the meaning of “to do (noun)”. 開始 = beginning -> 開始する = to begin; 勉強 = study -> 勉強する = to study and so forth.


Tae Kim covers it pretty early, but that’s not technically a textbook.

The stem when used by itself can be a very specialized and limited way of creating nouns from verbs. While the 「の」 particle allows you to talk about verbs as if they were nouns, the stem actually turns verbs into nouns.


Maybe it’s not taught because it is difficult to make an actual grammar rule out of it. Japanese is a very consistent language overall with very few exceptions, and in contrast to that it seems to me (and I’m a beginner so don’t take my word for it, more like an intuition) that this “stem = noun” pattern is more of a recurring thing than a rule.
It’s nice to notice it, in particular because it makes it easier to extend your vocabulary (as knowing the stem often times means knowing both a verb and a noun), but I’m not sure that thinking of it as a rule would help.
For instance (based on
歩き -> walking
走り -> running
読み -> reading
書き -> no result

Also, I’m guessing that sometimes it does create a proper noun but another one exists with the same meaning and is more natural to use. For instance, does return “swimming” for 泳ぎ, but in my (small) experience 水泳 would be a more common translation.

Anyway, this is also my first post on this forum, so hi everyone :slight_smile:


I don’t know how accurate this is but I found this on HiNative:

水泳&スイミング mean swimming as a sport.
泳ぎ means swimming which may or may not be a sport. It’s normally used for the ability to swim.


Oh nice, thanks for this.

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This makes me wonder. What is the difference between the nominalized form of a verb and the verb stem version. For example: 走るの or 走ること vs. 走り. As far as I can tell, it just seems like they all mean ‘running’.

It’s how “to run”, “a run” and “running” can all function as nouns in certain contexts, but have different uses.

More like, Japanese is as consistent as other languages. While the rules may seem consistent at the start, actual usage might not be.

Also, the stem = noun is an actual thing. The noun that’s created from some verb might not be in use, but it doesn’t mean it’s not a noun.


One rather neat thing is that some of these noun/verb pairs have different kanji, even though they come from the same word in Old Japanese.

Take for example 凍る (こおる), meaning “freeze”. Its ren’yōkei is 凍り, but when it is used to describe ice, it is spelled 氷.

There’s also 秤 (はかり), meaning “scale”, which comes from the ren’yōkei of 量る, meaning “to weigh”.
This word is also interesting because the verb uses different kanji depending on what is being measured: 量る for weight, 計る for time, and 測る for physical dimensions.
Presumably, Old Japanese used the same word for these three forms of measurement.

Wiktionary suggests the word 薬 (くすり), “medicine”, may be the ren’yōkei of an (unattested) word *kusuru, which would mean something like “to have a mystical effect”.

Then there are many more that use the same kanji, but the furigana is commonly omitted:

祭る -> 祭り -> 祭
話す -> 話し -> 話
踊る -> 踊り-> 踊
光る -> 光り -> 光


Like @konekush said, 走るの means to run but it’s usually used with ga like in 彼が走りのが安い. Adding の makes it act like a noun since you need a noun to precede が.

走ること is running as a concept. こと is like もの in that it means thing, but whereas もの is used for physical objects, like 食べもの, こと is for abstract concepts like the sentence 彼女はフルマラソンを走ることができる. Notice that it’s again acting like a noun because it’s used with が.

走りis the infinitive form or 連用形 (れんようけい). It’s like when you say, “I’m going running”. Here, “running” is the noun for the act of running. And when you search Jisho most of the sentences are using it with 回り as in 走り回る, to run around, which is a vocab word you learn at level 8.

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Thank you! The textbook that I’ve been using to learn just introduced the の and こと nominalizers together and didn’t really elucidate the difference between the two, so this was really helpful!

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Not sure this sentence makes sense. If you meant 走りやすい, I don’t think you can phrase it like that.

Pretty sure that was just a typo. Should have been 彼が走のが安い

Though, it is a bit ungrammatical in that you can’t use 安い regarding someone else’s opinion. :stuck_out_tongue:

To clarify this further, するのが and することが (with する being any verb in the dictionary form) can be used interchangeably for the most part. The exception comes when the following verb, the verb that comes after が, is related to perception (e.g., 聞く, 見る, 感じる, etc.) or happens in the same time frame as the following verb. の has to be used because it makes the clause that comes before it time-restrictive. On the other hand, if the following verb is related to communication or thoughts (e.g., 話す, 祈る, etc.), comes before the copula (e.g., 〜だ, 〜である, 〜です), or a set phrase (e.g., ことができる, etc.), then こと can only be used. In cases beyond these, either one can be used and still be grammatical.

This information is incomplete, so please refer to the following page.

I am assuming you meant 走の… But already mentioned by others. Also the use of 安い here surprises me. Does it have a different meaning from cheap in this context?

Continuative form? Infinitive is the jishokei, I think