This is the page that makes godan verbs click. The whole class runs on one idea: the final consonant of the stem is fixed, and each conjugation just chooses a vowel row for it. Learn the five-row set for one verb in a consonant column, and every other verb in that column falls out for free. Master the rows here and you have quietly pre-loaded half of intermediate conjugation, because the potential, volitional, and conditional forms are all just further stops on this same ladder.
The five bases of 書く
Let's take 書く（かく, "to write"), whose consonant is k. Watch the k never move while the vowel walks あ → い → う → え → お:
| Row | Base | Common form built on it | Result |
|---|---|---|---|
| あ (a) | 書か (kaka) | negative 〜ない | 書かない (kakanai) — doesn't write |
| い (i) | 書き (kaki) | polite 〜ます | 書きます (kakimasu) — writes |
| う (u) | 書く (kaku) | dictionary form | 書く (kaku) — to write |
| え (e) | 書け (kake) | conditional 〜ば / potential 〜る | 書けば (kakeba) / 書ける (kakeru) |
| お (o) | 書こ (kako) | volitional 〜う | 書こう (kakō) — let's write |
Five rows, five jobs. This is exactly the "五段 = five rows" that gives the class its name. Here is the full set in the wild:
最近は手紙をほとんど書かない。
saikin wa tegami o hotondo kakanai
These days I hardly write letters at all.
毎日日記を書きます。
mainichi nikki o kakimasu
I write in my diary every day.
メールはあとで書くね。
mēru wa ato de kaku ne
I'll write the email later, okay?
ひらがなはもう全部書ける。
hiragana wa mō zenbu kakeru
I can already write all of hiragana.
今年こそ小説を書こう。
kotoshi koso shōsetsu o kakō
This year for sure, I'm going to write a novel.
The same ladder, a different column: 飲む
Nothing above is special to 書く. Swap in 飲む（のむ, "to drink"), whose consonant is m, and the identical ladder appears one column over — か・き・く・け・こ simply becomes ま・み・む・め・も:
| Row | Base | Form | Result |
|---|---|---|---|
| あ | 飲ま (noma) | negative | 飲まない (nomanai) |
| い | 飲み (nomi) | polite | 飲みます (nomimasu) |
| う | 飲む (nomu) | dictionary | 飲む (nomu) |
| え | 飲め (nome) | conditional / potential | 飲めば (nomeba) / 飲める (nomeru) |
| お | 飲も (nomo) | volitional | 飲もう (nomō) |
運転するので、今日はお酒を飲まない。
unten suru node, kyō wa osake o nomanai
I'm driving, so I'm not drinking today.
今夜は乾杯して飲もう！
konya wa kanpai shite nomō
Tonight let's toast and have a drink!
The English-speaker takeaway is worth stating plainly: you do not memorize separate rules for "the negative of 飲む" and "the negative of 書く." You memorize one move — "negative = あ-row" — and apply it to whichever column the verb lives in. That is the entire economy of the godan system.
The whole grid
Here is the ladder across every godan consonant column. Read down a column to conjugate one verb; read across a row to see how a single form is built for all of them.
| Dictionary | あ (negative) | い (polite) | え (potential) | お (volitional) |
|---|---|---|---|---|
| 書く (kaku) | 書か (kaka) | 書き (kaki) | 書け (kake) | 書こ (kako) |
| 泳ぐ (oyogu) | 泳が (oyoga) | 泳ぎ (oyogi) | 泳げ (oyoge) | 泳ご (oyogo) |
| 話す (hanasu) | 話さ (hanasa) | 話し (hanashi) | 話せ (hanase) | 話そ (hanaso) |
| 待つ (matsu) | 待た (mata) | 待ち (machi) | 待て (mate) | 待と (mato) |
| 飲む (nomu) | 飲ま (noma) | 飲み (nomi) | 飲め (nome) | 飲も (nomo) |
| 作る (tsukuru) | 作ら (tsukura) | 作り (tsukuri) | 作れ (tsukure) | 作ろ (tsukuro) |
| 買う (kau) | 買わ (kawa) | 買い (kai) | 買え (kae) | 買お (kao) |
Three cells in this grid deserve a second look, because the kana chart hides a sound underneath a spelling:
- す column, い-row: 話し is "hanashi," not "hanasi." Japanese has no si sound, so the い-row of the s-column is し (shi). Hence 話します is hanashimasu.
- つ column: 待ち is "machi" and 待つ is "matsu." The t-column's い-row is ち (chi) and its う-row is つ (tsu) — the vowels are regular, the consonants just soften in Hepburn.
- う-verbs, あ-row: 買わ is "kawa," not "kaa." Verbs whose dictionary form ends in a bare う (買う, 会う, 使う) reach for わ on the あ-row, never あ. So the negative of 買う is 買わない (kawanai), not ×買あない.
週末に友だちと会おう。
shūmatsu ni tomodachi to aō
Let's meet up with friends this weekend.
そのスマホ、まだ使わないの？
sono sumaho, mada tsukawanai no
You're still not using that smartphone?
Why the rows are worth the investment
Everything on the higher-level conjugation pages is this ladder, continued. The potential form is the え-row + る (書ける, 飲める). The ば conditional is the え-row + ば (書けば, 飲めば). The volitional is the お-row + う (書こう, 飲もう). The polite ます is the い-row + ます, and the negative ない is the あ-row + ない. None of these are new systems — they are new endings bolted onto rows you already own.
Common mistakes
❌ 飲みない
Incorrect — the negative uses the あ-row, not the い-row.
✅ 飲まない
nomanai
I don't drink (it). (negative = あ-row 飲ま + ない)
❌ 買あない
Incorrect — う-verbs take わ on the あ-row, not あ.
✅ 買わない
kawanai
I won't buy (it). (買う → あ-row 買わ + ない)
❌ 書こます
Incorrect — the polite ます needs the い-row, not the お-row.
✅ 書きます
kakimasu
I write. (polite = い-row 書き + ます)
❌ 話さう
Incorrect — the volitional う needs the お-row, not the あ-row.
✅ 話そう
hanasō
Let's talk. (volitional = お-row 話そ + う)
Every mistake here is a mis-selected row: the right ending attached to the wrong rung. That is the only error godan verbs can really produce — which is why this single ladder is worth over-learning.
Key takeaways
- A godan verb keeps its consonant fixed and picks a vowel row for each conjugation.
- The five bases: あ = negative (飲まない), い = polite (飲みます), う = dictionary (飲む), え = potential/conditional (飲める・飲めば), お = volitional (飲もう).
- Learn the ladder for one verb per column and every verb in that column follows.
- Watch the three spelling traps: し (not si), ち/つ (not ti/tu), and わ on the あ-row of う-verbs (買わない, not ×買あない).
- Potential, conditional, and volitional are just more endings on rows you already know.
Now practice Japanese
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning Japanese→Related Topics
- Godan (五段) VerbsN5 — The largest verb class, whose stem ends in a consonant and whose final kana shifts across all five vowel rows.
- Forming 〜ない Across the ClassesN4 — The mechanical rule for the plain negative — godan to the あ-row (with わ for う-verbs), ichidan drop-る, and the two irregulars — plus the ある → ない exception.
- Forming ます Across the ClassesN4 — The mechanical rule for building the ます-stem in every verb class — the godan い-row kana shift, the ichidan る-drop, and the two irregulars — so ます becomes automatic.