Ichidan vs. Godan Verbs

In Japanese, two major groups of verbs are ichidan verbs and godan verbs, and a major doubt of many beginners is: what's the difference between godan and ichidan? How do you tell if a verb is ichidan or godan? What do the words ichidan and godan mean?

The answer for these three questions is conjugation, conjugation, and conjugation. But I suppose I should explain it in more detail.

• Endings
• Conjugation
• Name
• Transitive-Intransitive Verb Pairs

Verb Groups

In Japanese, verbs are sometimes divided into group 1, group 2, and group 3, or type 1, type 2, type 3, or class 1, class 2, class 3, ichi-guruupu Iグループ, ni-guruupu IIグループ, san-guruupu IIIグループ, or whatever in the world your teacher, book, resource, material, or blog is calling it now.

Point is: there are three groups of verbs in modern, standard Japanese, which group verbs according to their conjugation, and for some reason are always, consistently enumerated in the following order:

1. godan verbs, also called consonant-stem verbs,
2. ichidan verbs, also called vowel-stem verbs, which always end in ~eru or ~iru.
3. The rest. Which are only two verbs: suru する and kuru 来る, which are also called irregular verbs.

As long as you aren't reading some poem from the 9th century, any verb you find in Japanese will fall into one of the three groups above. In other words, if you know how to conjugate the three groups, you know how to conjugate any verb in Japanese.

See also: ichidan vs. godan verbs.

Irregular Verbs

Among verb types, irregular verbs are verbs whose conjugation is non-standard, and doesn't follow the usual conjugation rules that basically every other verb in the language follows.

The Japanese language is often said to have only two irregular verbs: suru する, "to do," and kuru 来る, "to come," which are also called "group 3 verbs," among the three groups of verbs in Japanese, the other two being godan verbs and ichidan verbs, whose conjugation would be regular.

Besides those, the words aru ある, nai ない, yoi よい, ii いい, and iku 行く also feature irregularities to watch out for. So I'm listing all of them here.

• Grammar
• Conjugation
  
  • 来る
  • する
  • ある
  • 無い
  • 行く
  • いい
  • よい

Ichidan Verbs

In Japanese, ichidan verbs are verbs that end in ~eru and ~iru, which undergo ichidan katsuyou 一段活用, "one-column conjugation." This means that, when conjugated, their stem ends at the vowel, ~e or ~i, and it's always that same one vowel, no matter what suffixes are attached to it.

They're also called "group 2 verbs," among the three groups of verbs that exist in Japanese.

• 上一段・下一段
• Conjugation
  
  • Dialects
  • History
  • Auxiliaries

Godan Verbs

In Japanese, godan verbs are verbs which undergo godan katsuyou 五段活用, "five-column conjugation." This means that, when conjugated, their stem ends at the consonant, and the vowel of the last syllable can change into any of the five vowels: a-i-u-e-o.

They're also called "group 1 verbs," among the three groups of verbs that exist in Japanese.

• Endings
• Conjugation
  
  • Past Form and Te-Form
  • Polite Form
  • ～う Ending
  • ～る Ending

Changes in Pronunciation

In Japanese, sometimes words are pronounced in a way different from how you'd expect them to be pronounced. This specially happens at the boundary of two morphemes forming a word.

For example, combining the number "one," ichi 一, with the counter for shots, hatsu 発, gets you ippatsu 一発, not ichi-hatsu. Combining the ren'youkei 連用形 form of shinu 死ぬ, shini 死に, with the jodoushi 助動詞 ~ta ～た gets you shinda 死んだ, not shini-ta.

• Types
• Orthography
  
  • Informal Changes
  • Formal Changes
    
    • Grammatical Changes
  • Prescribed Lies
  • Intensifying Changes
• References

Long Vowels

In Japanese, long vowels, or "long sounds," chouon 長音, refer to vowels pronounced for twice as long than normal. See also: mora. The opposite are short vowels, or "short sounds," tan'on 短音.

For example, ko こ has a short vowel, while kou こう, koo こー, and koo こぉ have long vowels.

• Orthography
  
  • 長音化
  • 短母音化
  • Mimetic Words

Mora

In Japanese, one mora is the length of time it usually takes to pronounce one kana 仮名, although there are exceptions.

• Grammar
• Rules
  
  • Syllabeme Dialects
• In Poetry
• Japanese Terms
• References

四つ仮名

In Japanese, yotsugana 四つ仮名, refers to ji じ, di ぢ, zu ず, and dzu づ. These "four kana 仮名," were originally pronounced distinctly, but in modern Japanese, in some regions of Japan, they're all pronounced the same way, they've become homonyms.

Manga: Azumanga Daioh あずまんが大王 (Volume 1, Chapter 8, August: Part 2, Page 84, ぶち壊しさわやか)

• Usage
• Orthography
  
  • Romanization
• References

半濁音化

In Japanese, handakuonka 半濁音化 is a change in pronunciation similar to rendaku 連濁 in which the syllables ha-hi-fu-he-ho はひふへほ get a handakuten 半濁点, turning into the semi-voiced pa-pi-pu-pe-po ぱぴぷぺぽ.

For example: kinpatsu きんぱつ (金髪), "golden hair, "blond," which combines the morphemes "gold" and "hair," kin きん and hatsu はつ, or ippatsu いっぱつ (一発), "one shot," which combines "one" and "shot," ichi いち and hatsu はつ.

• Examples
• Grammar
• References

tenten 点々

In Japanese, tenten 点々 means "dots" or "points." It's a reduplication of ten 点, which means a "dot" or "point."

The word is sometimes used to refer to symbols that look like dots, such as dakuten 濁点 (゛) and the ditto mark (〃), which are also called chonchon ちょんちょん, *striking repeatedly* (phenomime), due to how your hand moves in order to write them.

Manga: Hikaru no Go ヒカルの碁 (Chapter 1, 棋聖降臨)

• miro yo
  見ろよ
  Look!
• koko ni chi no ato mitai ni ten-ten to......
  ここに血のアトみたいに点々と･･････
  In here, [something that] looks like blood marks [is stuck] in drops.
  • ato 跡
    Something left behind by something else, usually as evidence.
    Tracks, traces, marks, scars, etc.
  • tenten to 点々と
    Scattered around as spots, dots, points.

転音

In Japanese, ten'on 転音, also called boin koutai 母音交替, "vowel change," is a change in pronunciation where the vowel of a morpheme changes in order to connect to another morpheme in a word.

Examples include:

• fune-ashi ふねあし
  funaashi ふなあし (舟足)
  Boat speed.
• kaze-kami かぜかみ
  kazakami かざかみ (風上)
  Upwind.
• kami-nagara かみながら
  kamunagara かむながら
  As a god.
  As in the age of gods.
• ame-kasa あめかさ
  amagasa あまがさ (雨傘)
  Umbrella.
• sake-taru さけたる
  sakadaru さかだる (酒樽)
  Alcohol barrel, cask.
• ue-ki うえき
  uwagi うわぎ (上着)
  Outer garment. Coat.
• ki-tachi きたち
  kodachi こだち (木立)
  Tree grove.

Note: in the words above, ka becoming ga, ta becoming da, and ki becoming gi consist of a different change in pronunciation called rendaku 連濁.

onbinkei 音便形

In Japanese onbinkei 音便形 is a verb form that has been affected by onbin 音便, by changes in pronunciation. This term is used to distinguish between the original forms and forms that were changed due to euphony.

In general, onbin seems to affect only the ren'youkei 連用形 form of verbs and adjectives. So you have the normal ren'youkei form, and the distorted onbinkei form.

• 五段
  
  • Before ます
• Adjectives
• 四段
• Dialects

onbin 音便

In Japanese, onbin 音便, often translated as "euphonic change," refers to four types of changes in pronunciation that affect, among other things, the ren'youkei 連用形 conjugation of verbs. Such changes exist to make the words easier to pronounce. They are:

1. u-onbin
   ウ音便
   Changes a kana to u う.
   Example: omohi-te 思ひて
   Becomes: omoute 思うて.
2. i-onbin
   イ音便
   Changes a kana to i い.
   Example: kaki-te 書きて
   Becomes: kaite 書いて.
3. hatsuonbin
   撥音便
   Changes a kana to n ん. This n ん is called hatsuon.
   Example: shini-te 死にて
   Becomes: shinde 死んで.
4. sokuonbin
   促音便
   Changes a kana to the small tsu っ, which represents a "geminate consonant," sokuon 促音.
   Example: tori-te 取りて
   Becomes: totte 取って.

See onbinkei 音便形 for a more complete list of uses.

According to the dictionary Nihon Kokugo Daijiten 日本国語大辞典, Motoori Norinaga 本居宣長 (1730–1801) was the scholar that introduced the onbin terms to Japanese grammar. When he did so, he also included the rendaku 連濁 in the definition of onbin.^{[音便 - kotobank.jp, accessed 2019-11-10]}

連声濁

In Japanese, renjoudaku 連声濁 is a change in pronunciation similar to rendaku 連濁, where the first syllable of a suffix gets a "diacritic," dakuten 濁点. Unlike rendaku, renjoudaku merges a nasal or voiced syllable with another syllable, and can affect syllables beyond suffixes.

For example: nado など, "et cetera," comes from nani-to なにと, or nanto なんと. While shinda 死んだ, "died," comes from shini-ta 死にた.

• Definition
• 連用形
• Other Words
• References