Editing Japanese grammar (section)

==Conjugable words==

===Stem forms===
Conjugative suffixes and auxiliary verbs are attached to the stem forms of the affixee. In modern Japanese, there are six stem forms, ordered following from the {{transliteration|ja|-a, -i, -u, -e, -o}} endings that these forms have in {{nihongo|5-row|五段}} verbs (according to the {{lang|ja|あ、い、う、え、お}} collation order of Japanese), where terminal and attributive forms are the same for verbs (hence only 5 surface forms), but differ for nominals, notably {{transliteration|ja|na}}-nominals.
; {{nihongo|''Irrealis form''|未然形|mizenkei}} {{transliteration|ja|-a}} (and {{transliteration|ja|-ō}}): is used for plain negative (of verbs), causative and passive constructions. The most common use of this form is with the {{transliteration|ja|-nai}} auxiliary that turns verbs into their negative (predicate) form. (See Verbs below.) The {{transliteration|ja|-ō}} version is used for volitional expression and formed by a {{nihongo|euphonic change|音便|onbin}}.
; {{nihongo|''Continuative form''|連用形|ren'yōkei}} {{transliteration|ja|-i}}: is used in a linking role (a kind of [[serial verb construction]]). This is the most productive stem form, taking on a variety of endings and auxiliaries, and can even occur independently in a sense similar to the {{transliteration|ja|-te}} ending. This form is also used to negate adjectives.
; {{nihongo|''Terminal form''|終止形|shūshikei}} {{transliteration|ja|-u}}: is used at the ends of clauses in [[predicate (grammar)|predicate]] positions. This form is also variously known as {{nihongo|''plain form''|基本形|kihonkei}} or {{nihongo|''[[dictionary form]]''|辞書形|jishokei}} – it is the form that verbs are listed under in a dictionary.
; {{nihongo|''[[Attributive verb#Japanese|{{vanchor|Attributive form}}]]''|{{vanchor|連体形}}|rentaikei}} {{transliteration|ja|-u}}: is prefixed to nominals and is used to define or classify the noun, similar to a [[relative clause]] in English. In modern Japanese it is practically identical to the terminal form, except that verbs are generally not inflected for politeness; in old Japanese these forms differed. Further, {{transliteration|ja|na}}-nominals behave differently in terminal and attributive positions; see [[#Adjectival verbs and nouns|Adjectival verbs and nouns]], below.
; {{nihongo|''Hypothetical form''|仮定形|kateikei}} {{transliteration|ja|-e}}: is used for conditional and subjunctive forms, using the {{transliteration|ja|-ba}} ending.
; {{nihongo|''Imperative form''|命令形|meireikei}} {{transliteration|ja|-e}}: is used to turn verbs into commands. Adjectives do not have an imperative stem form.

The application of conjugative suffixes to stem forms follow certain {{nihongo|euphonic principles|音便|onbin}}.

===Verbs===
{{Main|Japanese verb conjugation}}

{{nihongo|Verbs|動詞|dōshi}} in Japanese are rigidly constrained to the end of a clause. This means that the ''predicate position'' is always located at the end of a sentence.

{{fs interlinear|lang=ja|indent=3|glossing=no abbr
|猫 は 魚 を 食べる
|Neko wa sakana o taberu
|Cat TOPIC fish OBJECT eat
|"A cat eats fish"}}

The subject and objects of the verb are indicated by means of ''[[Japanese grammar#Particles|particles]]'', and the grammatical functions of the verb (primarily tense and voice) are indicated by means of [[Grammatical conjugation|conjugation]]. When the subject and the dissertative topic coincide, the subject is often omitted; if the verb is intransitive, the entire sentence may consist of a single verb. Verbs have two tenses indicated by conjugation, past and non-past. The semantic difference between present and future is not indicated by means of conjugation. Usually there is no ambiguity as context makes it clear whether the speaker is referring to the present or future. Voice and aspect are also indicated by means of conjugation, and possibly agglutinating auxiliary verbs. For example, the continuative aspect is formed by means of the continuative conjugation known as the ''gerundive'' or ''[[te form of Japanese verb|{{transliteration|ja|-te}} form]]'', and the auxiliary verb {{nihongo3|"to be"||iru}}; to illustrate, {{nihongo3|"to see"|見る|miru}} → {{nihongo3|"to be seeing"|見ている|mite iru}}.

Verbs can be semantically classified based on certain conjugations.
; Stative verbs: indicate existential properties, such as {{nihongo|"to be"|いる|iru}}, {{nihongo|"to be able to do"|出来る|dekiru}}, {{nihongo|"to need"|要る|iru}}, etc. These verbs generally do not have a continuative conjugation with {{transliteration|ja|-iru}} because they are semantically continuative already.
; Continual verbs: conjugate with the auxiliary {{transliteration|ja|-iru}} to indicate the progressive aspect. Examples: {{nihongo|"to eat"|食べる|taberu}}, {{nihongo|"to drink"|飲む|nomu}}, {{nihongo|"to think"|考える|kangaeru}}. To illustrate the conjugation, {{nihongo3|"to eat"|食べる|taberu}} → {{nihongo3|"to be eating"|食べている|tabete iru}}.
; Punctual verbs: conjugate with {{transliteration|ja|-iru}} to indicate a repeated action, or a continuing state after some action. Example: {{nihongo3|"to know"|知る|shiru}} → {{nihongo3|"to be knowing"|知っている|shitte iru}}; {{nihongo3|"to hit"|打つ|utsu}} → {{nihongo3|"to be hitting (repeatedly)"|打っている|utte iru}}.
; Non-volitional verb: indicate uncontrollable action or emotion. These verbs generally have no volitional, imperative or potential conjugation. Examples: {{nihongo3|"to like / to prefer" [emotive]|好む|konomu}}, {{nihongo3|"to be visible" [non-emotive]|見える|mieru}}.
; Movement verbs: indicate motion. Examples: {{nihongo3|"to walk"|歩く|aruku}}, {{nihongo3|"to return"|帰る|kaeru}}. In the continuative form (see [[Japanese grammar#Verbal adverbs|§ Verbal adverbs]]) they take the particle {{transliteration|ja|ni}} to indicate a purpose.
There are other possible classes, and a large amount of overlap between the classes.

Lexically, nearly every verb in Japanese is a member of exactly one of the following three regular ''conjugation groups'' (see also [[Japanese godan and ichidan verbs]]).
; {{nihongo|Group 2a|上一段|kami ichidan|lit. upper 1-row}}: verbs with a stem ending in {{transliteration|ja|-i}}. The terminal stem form always rhymes with {{transliteration|ja|-iru}}. Examples: {{nihongo3|"to see"|見る|miru}}, {{nihongo3|"to wear"|着る|kiru}}.
; {{nihongo|Group 2b|下一段|shimo ichidan|lit. lower 1-row}}: verbs with a stem ending in {{transliteration|ja|-e}}. The terminal stem form always rhymes with {{transliteration|ja|-eru}}. Examples: {{nihongo3|"to eat"|食べる|taberu}}, {{nihongo3|"to give" (to someone of lower or more intimate status)|くれる|kureru}}. (Some Group 1 verbs resemble Group 2b verbs, but their stems end in {{transliteration|ja|r-}}, not {{transliteration|ja|-e}}.)
; {{nihongo|Group 1|五段|godan|lit. 5-row}}: verbs with a stem ending in a consonant. When this is {{transliteration|ja|r-}} and the verb ends in {{transliteration|ja|-eru}}, it is not apparent from the terminal form whether the verb is Group 1 or Group 2b, e.g. {{nihongo3|"to return"|帰る|kaeru}}. If the stem ends in {{transliteration|ja|w-}}, that consonant sound only appears in before the final {{transliteration|ja|-a}} of the [[irrealis]] form.

The "row" in the above classification means a row in the [[gojūon]] table. "Upper 1-row" means the row that is one row above the center row (the {{transliteration|ja|u}}-row) i.e. i-row. "Lower 1-row" means the row that is one row below the center row (the {{transliteration|ja|u}}-row) i.e. {{transliteration|ja|e}}-row. "5-row" means the conjugation runs through all 5 rows of the [[gojūon]] table. A conjugation is fully described by identifying both the row and the column in the [[gojūon]] table. For example, {{nihongo3|"to see"|見る|miru}} belongs to {{nihongo3|{{transliteration|ja|ma}}-column {{transliteration|ja|i}}-row conjugation|マ行上一段活用}}, {{nihongo3|"to eat"|食べる|taberu}} belongs to {{nihongo3|{{transliteration|ja|ba}}-column {{transliteration|ja|e}}-row conjugation|バ行下一段活用}}, and {{nihongo3|"to return"|帰る|kaeru}} belongs to {{nihongo3|{{transliteration|ja|ra}}-column 5-row conjugation|ラ行五段活用}}.

One should avoid confusing verbs in {{nihongo3|{{transliteration|ja|ra}}-column 5-row conjugation|ラ行五段活用}} with verbs in {{nihongo3|{{transliteration|ja|i}}-row conjugation|上一段活用}} or {{nihongo|{{transliteration|ja|e}}-row conjugation|下一段活用}}. For example, {{nihongo3|"to cut"|切る|kiru}} belongs to {{nihongo|{{transliteration|ja|ra}}-column 5-row conjugation|ラ行五段活用}}, whereas its homophone {{nihongo3|"to wear"|着る|kiru}} belongs to {{nihongo|{{transliteration|ja|ka}}-column {{transliteration|ja|i}}-row conjugation|カ行上一段活用}}. Likewise, {{nihongo3|"to knead"|練る|neru}} belongs to {{nihongo|{{transliteration|ja|ra}}-column 5-row conjugation|ラ行五段活用}}, whereas its homophone {{nihongo3|"to sleep"|寝る|neru}} belongs to {{nihongo|{{transliteration|ja|na}}-column {{transliteration|ja|e}}-row conjugation|ナ行下一段活用}}.

Historically, Classical Japanese had {{nihongo|upper and lower 1-[[row group]]s|上・下一段|kami/shimo ichidan}}, {{nihongo|upper and lower 2-row groups|上・下二段|kami/shimo nidan}} and a {{nihongo|4-row group|四段|yodan}}. The {{transliteration|ja|nidan}} verbs became most of the {{transliteration|ja|ichidan}} verbs in modern Japanese (only a handful of {{transliteration|ja|kami ichidan}} verbs and a single {{transliteration|ja|shimo ichidan}} verb existed in classical Japanese). The {{transliteration|ja|yodan}} group was reclassified as the {{transliteration|ja|godan}} group during the post-WWII writing reform in 1946, to write Japanese as it is pronounced. Since verbs have migrated across groups in the history of the language, the conjugation of classical verbs cannot be ascertained from knowledge of modern Japanese alone.

Of the irregular classes, there are two:
; {{transliteration|ja|sa}}-group: which has only one member, {{nihongo3|"to do"|する|suru}}. In Japanese grammars these words are classified as {{nihongo3||サ変|sa-hen}}, an abbreviation of {{nihongo3||サ行変格活用|sa-gyō henkaku katsuyō}}, sa-row irregular conjugation).
; {{transliteration|ja|ka}}-group: which also has one member, {{nihongo3|"to come"|来る|kuru}}. The Japanese name for this class is {{nihongo3||カ行変格活用|ka-gyō henkaku katsuyō}} or simply {{nihongo3||カ変|ka-hen}}.
Classical Japanese had two further irregular classes, the {{transliteration|ja|na}}-group, which contained {{nihongo3|"to die"|死ぬ|shinu}} and {{nihongo3|"to go"/"to die"|往ぬ|inu}}, the {{transliteration|ja|ra}}-group, which included such verbs as {{nihongo3||あり|ari}}, the equivalent of modern {{transliteration|ja|aru}}, as well as quite a number of extremely irregular verbs that cannot be classified.

The following table illustrates the stem forms of the above conjugation groups, with the root indicated with dots. For example, to find the hypothetical form of the group 1 verb {{nihongo3||書く|kaku}}, look in the second row to find its root, {{transliteration|ja|kak-}}, then in the hypothetical row to get the ending {{transliteration|ja|-e}}, giving the stem form {{transliteration|ja|kake}}. When there are multiple possibilities, they are listed in the order of increasing rarity.

{| class="wikitable" style="text-align:center;"
|+
!Group
! colspan="2" |1
!2a
!2b
! rowspan="2" |{{transliteration|ja|sa}}
! rowspan="2" |{{transliteration|ja|ka}}
|-
!Example
!{{nihongo||使・|tsuka(w).}}
!{{nihongo||書・|kak.}}
!{{nihongo||見・|mi.}}
!{{nihongo||食べ・|tabe.}}
|-
!{{nihongo|Irrealis form<sup>1</sup>{{pb}}|未然形|mizenkei}}
|{{nihongo||使わ|tsukaw.a}}<sup>2</sup>{{pb}}{{nihongo||使お|tsuka.o}}
|{{nihongo||書か|kak.a}}{{pb}}{{nihongo||書こ|kak.o}}
|{{nihongo||見|mi.}}
|{{nihongo||食べ|tabe.}}
|{{nihongo||さ|sa}}{{pb}}{{nihongo||し|shi}}{{pb}}{{nihongo||せ|se}}
|{{nihongo||来|ko}}
|-
!{{nihongo|Continuative form{{pb}}|連用形|ren'yōkei}}
|{{nihongo||使い|tsuka.i}}
|{{nihongo||書き|kak.i}}
|{{nihongo||見|mi.}}
|{{nihongo||食べ|tabe.}}
|{{nihongo||し|shi}}
|{{nihongo||来|ki}}
|-
!{{nihongo|Terminal form{{pb}}|終止形|shūshikei}}
|{{nihongo||使う|tsuka.u}}
|{{nihongo||書く|kak.u}}
|{{nihongo||見る|mi.ru}}
|{{nihongo||食べる|tabe.ru}}
|{{nihongo||する|suru}}
|{{nihongo||来る|kuru}}
|-
!Attributive form
| colspan="6" |Same as terminal form
|-
!{{nihongo|Hypothetical form{{pb}}|仮定形|kateikei}}
|{{nihongo||使え|tsuka.e}}
|{{nihongo||書け|kak.e}}
|{{nihongo||見れ|mi.re}}
|{{nihongo||食べれ|tabe.re}}
|{{nihongo||すれ|sure}}
|{{nihongo||来れ|kure}}
|-
!{{nihongo|Imperative form{{pb}}|命令形|meireikei}}
|{{nihongo||使え|tsuka.e}}
|{{nihongo||書け|kak.e}}
|{{nihongo||見ろ|mi.ro}}{{pb}}{{nihongo||見よ|mi.yo}}
|{{nihongo||食べろ|tabe.ro}}{{pb}}{{nihongo||食べよ|tabe.yo}}
|{{nihongo||しろ|shiro}}{{pb}}{{nihongo||せよ|seyo}}{{pb}}{{nihongo||せい|sei}}
|{{nihongo||来い|koi}}
|}

# The {{transliteration|ja|-a}} and {{transliteration|ja|-o}} irrealis forms for Group 1 verbs were historically one, but since the post-WWII spelling reforms they have been written differently. In modern Japanese the {{transliteration|ja|-o}} form is used only for the volitional mood and the {{transliteration|ja|-a}} form is used in all other cases; see also the conjugation table below.
# The unexpected ending is due to the verb's root being {{transliteration|ja|tsukaw-}} but {{transliteration|ja|w-}} only being pronounced before {{transliteration|ja|-a}} in modern Japanese.

The above are only the stem forms of the verbs; to these one must add various verb endings in order to get the fully conjugated verb. The following table lists the most common conjugations. Note that in some cases the form is different depending on the conjugation group of the verb. See [[Japanese verb conjugation]]s for a full list.

{| class="wikitable" style="text-align:center"
! rowspan="2"| &nbsp;
! rowspan="2"| formation rule
! group 1
! group 2a
! group 2b
! {{transliteration|ja|sa}}-group
! {{transliteration|ja|ka}}-group
|-
! {{nihongo||書く|kaku}}
! {{nihongo||見る|miru}}
! {{nihongo||食べる|taberu}}
! {{nihongo||する|suru}}
! {{nihongo||来る|kuru}}
|-
! polite{{pb}}[[imperfective aspect|imperfective]]
| cont. + {{nihongo||ます|masu}}
| {{nihongo||書き・ます|kaki.masu}}
| {{nihongo||見・ます|mi.masu}}
| {{nihongo||食べ・ます|tabe.masu}}
| {{nihongo||し・ます|shi.masu}}
| {{nihongo||来・ます|ki.masu}}
|-
! plain{{pb}}[[perfective aspect|perfective]]
| cont. + {{nihongo||た|ta}}
| {{nihongo||書い・た|kai.ta}}<sup>2</sup>
| {{nihongo||見・た|mi.ta}}
| {{nihongo||食べ・た|tabe.ta}}
| {{nihongo||し・た|shi.ta}}
| {{nihongo||来・た|ki.ta}}
|-
! plain{{pb}}negative{{pb}}[[imperfective aspect|imperfective]]
| irrealis + {{nihongo||ない|nai}}
| {{nihongo||書か・ない|kaka.nai}}
| {{nihongo||見・ない|mi.nai}}
| {{nihongo||食べ・ない|tabe.nai}}
| {{nihongo||し・ない|shi.nai}}
| {{nihongo||来・ない|ko.nai}}
|-
! plain{{pb}}negative{{pb}}[[perfective aspect|perfective]]
| irrealis + {{nihongo||なかった|nakatta}}
| {{nihongo||書か・なかった|kaka.nakatta}}
| {{nihongo||見・なかった|mi.nakatta}}
| {{nihongo||食べ・なかった|tabe.nakatta}}
| {{nihongo||し・なかった|shi.nakatta}}
| {{nihongo||来・なかった|ko.nakatta}}
|-
! {{transliteration|ja|-te}} form (gerundive)
| cont. + {{nihongo||て|-te}}
| {{nihongo||書いて|kai.te}}<sup>2</sup>
| {{nihongo||見て|mi.te}}
| {{nihongo||食べて|tabe.te}}
| {{nihongo||して|shi.te}}
| {{nihongo||来て|ki.te}}
|-
! provisional{{pb}}conditional
| hyp. + {{nihongo||ば|ba}}
| {{nihongo||書け・ば|kake.ba}}
| {{nihongo||見れ・ば|mire.ba}}
| {{nihongo||食べれ・ば|tabere.ba}}
| {{nihongo||すれ・ば|sure.ba}}
| {{nihongo||来れ・ば|kure.ba}}
|-
! past{{pb}}conditional
| cont. + {{nihongo||たら|tara}}
| {{nihongo||書いたら|kai.tara}}<sup>2</sup>
| {{nihongo||見たら|mi.tara}}
| {{nihongo||食べたら|tabe.tara}}
| {{nihongo||したら|shi.tara}}
| {{nihongo||来たら|ki.tara}}
|-
!rowspan="2"| volitional
| irrealis + {{nihongo||う|u}}
| {{nihongo||書こ・う|kako.u}}
|colspan="4"|
|-
| irrealis + {{nihongo||よう|yō}}
|
| {{nihongo||見・よう|mi.yō}}
| {{nihongo||食べ・よう|tabe.yō}}
| {{nihongo||し・よう|shi.yō}}
| {{nihongo||来・よう|ko.yō}}
|-
!rowspan="2"| passive
| irrealis + {{nihongo||れる|reru}}
| {{nihongo||書か・れる|kaka.reru}}
|colspan="2"|
| {{nihongo||さ・れる|sa.reru}}
|
|-
| irrealis + {{nihongo||られる|rareru}}
|
| {{nihongo||見・られる|mi.rareru}}
| {{nihongo||食べ・られる|tabe.rareru}}
|
| {{nihongo||来・られる|ko.rareru}}
|-
!rowspan="2"| causative
| irrealis + {{nihongo||せる|seru}}
| {{nihongo||書か・せる|kaka.seru}}
|colspan="2"|
| {{nihongo||さ・せる|sa.seru}}
|
|-
| irrealis + {{nihongo||させる|saseru}}
|
| {{nihongo||見・させる|mi.saseru}}
| {{nihongo||食べ・させる|tabe.saseru}}
|
| {{nihongo||来・させる|ko.saseru}}
|-
!rowspan="2"| potential
| hyp. + {{nihongo||る|ru}}
| {{nihongo||書け・る|kake.ru}}
|colspan="2"|
| {{nihongo||出来る|dekiru}}<sup>1</sup>
|
|-
| irrealis + {{nihongo||られる|rareru}}
|
| {{nihongo||見・られる|mi.rareru}}
| {{nihongo||食べ・られる|tabe.rareru}}
|
| {{nihongo||来・られる|ko.rareru}}
|}

# This is an entirely different verb; {{nihongo||する|suru}} has no potential form.
# These forms change depending on the final syllable of the verb's dictionary form (whether {{transliteration|ja|u, ku, gu, su,}} etc.). For details, see [[#Euphonic changes (音便, onbin)|Euphonic changes]], below, and the article [[Japanese verb conjugation]].

The polite ending {{transliteration|ja|-masu}} conjugates as a group 1 verb, except that the negative imperfective and perfective forms are {{transliteration|ja|-masen}} and {{transliteration|ja|-masen deshita}} respectively, and certain conjugations are in practice rarely if ever used. The passive and potential endings {{transliteration|ja|-reru}} and {{transliteration|ja|-rareru}}, and the causative endings {{transliteration|ja|-seru}} and {{transliteration|ja|-saseru}} all conjugate as group 2b verbs. Multiple verbal endings can therefore agglutinate. For example, a common formation is the ''causative-passive'' ending: {{transliteration|ja|-sase-rareru}}.

{{fs interlinear|lang=ja|indent=3
|僕 は 姉 に 納豆 を 食べさせられた。
|Boku wa ane ni nattō o tabe'''saserareta'''.
|I '''was made to''' eat {{transliteration|ja|[[nattō]]}} by my (elder) sister.}}

As should be expected, the vast majority of theoretically possible combinations of conjugative endings are not semantically meaningful.

====Transitive and intransitive verbs====
Japanese has a large variety of related pairs of [[transitive verb]]s (that take a direct object) and [[intransitive verb]]s (that do not usually take a direct object), such as the transitive {{nihongo3|someone or something begins an activity|始める|hajimeru}}, and the intransitive {{nihongo3|an activity begins|始まる|hajimaru}}.<ref>[http://www.sljfaq.org/afaq/jitadoushi.html "What's the difference between hajimeru and hajimaru?"] in ''sci.lang.japan Frequently Asked Questions''</ref><ref>Kim Allen (2000) [http://kimallen.sheepdogdesign.net/Japanese/verbs2.html "Japanese verbs, part 2"] {{Webarchive|url=https://web.archive.org/web/20070810194203/http://kimallen.sheepdogdesign.net/Japanese/verbs2.html |date=2007-08-10}} in ''Japanese for the Western Brain''</ref>

{| class="wikitable"
|+
!transitive verb
!intransitive verb
|-
|
* One thing acts out the transitive verb on another
* Usually uses {{nihongo||を|o}} to link to the direct object
|
* The intransitive verb passively happens without direct intervention.
* Usually uses {{nihongo||が|ga}} or {{nihongo||は|wa}} to link subject and verb.
|-
|{{fs interlinear|lang=ja|先生 が 授業 を 始める。|Sensei ga jugyō o hajimeru.|The teacher starts the class.}}
|{{fs interlinear|lang=ja|授業 が 始まる。|Jugyō ga hajimaru.|The class starts.}}
|-
|{{fs interlinear|lang=ja|車 に 何 か を 入れる|Kuruma ni nani ka o ireru|To put something in the car}}
|{{fs interlinear|lang=ja|車 に 入る|Kuruma ni hairu|To enter the car}}
|-
|{{nihongo3|'to take/put out'|出す|dasu}}
|{{nihongo3|'to exit'|出る|deru}}
|-
|{{nihongo3|'to extinguish'|消す|kesu}}
|{{nihongo3|'to go out'|消える|kieru}}
|-
|{{nihongo3|'to open [something]'|開ける|akeru}}
|{{nihongo3|'to open'/'to be open'|開く|aku}}
|-
|{{nihongo3|'to attach [something]'|付ける|tsukeru}}
|{{nihongo3|'to attach'/'to be attached'|付く|tsuku}}
|-
|{{nihongo3|'to close [something]'|閉める|shimeru}}
|{{nihongo3|'to close'/'to be closed'|閉まる|shimaru}}
|-
|{{nihongo3|'to find'|見つける|mitsukeru}}
|{{nihongo3|'to be found'|見つかる|mitsukaru}}
|-
|{{nihongo3|'to extract'|抜く|nuku}}
|{{nihongo3|'to come out'|抜ける|nukeru}}
|-
|{{nihongo3|'to wake [someone] up'|起こす|okosu}}
|{{nihongo3|'to wake up'|起きる|okiru}}
|-
|{{nihongo3|'to give birth'|生む|umu}}
|{{nihongo3|'to be born'|生まれる|umareru}}
|}

Note: Some intransitive verbs (usually verbs of motion) take what looks like a direct object, but is not.<ref>{{cite journal |last=早津 |first=恵美子 |date=1 December 1987 |editor1=壇辻正剛 |editor2=楢崎勝則 |title=Taiō suru tadōshi no aru jidōshi no imiteki tōgoteki tokuchō |script-title=ja:対応する他動詞のある自動詞の 意味的・統語的特徴 |trans-title=Semantic and syntactic characteristics of intransitive verbs that have corresponding transitive verbs |url=https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/87929/1/gen00006_079.pdf |department=論文 |journal=Gengogaku kenkyū |script-journal=ja:言語学研究 |trans-journal=Linguistic Research<!--this translation is the official english name of the journal--> |language=ja |volume=6 |publisher=京都大学言語学研究会 (Kyōto daigaku gengogaku kenkyūkai) [Kyoto University Linguistics Circle<!--this translation is the official english name of the publisher-->] |pages=79-109 |url-status=live |archive-url=https://web.archive.org/web/20240529161801/https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/87929/1/gen00006_079.pdf |archive-date=29 May 2024 |access-date=18 May 2025 |hdl=2433/87929 |hdl-access=free |issn=0915-6178 |id={{NAID|120001712186}}}}</ref> For example, {{nihongo3|to leave|離れる|hanareru}}:

{{fs interlinear|lang=ja|indent=3
|私 は 東京 を 離れる。
|Watashi wa Tōkyō o hanareru.
|I leave Tokyo.}}

{{anchor|Adjectives|adjectives}}

===Adjectival verbs and nouns===
{{Main|Japanese adjectives}}

Semantically speaking, words that denote attributes or properties are primarily distributed between two morphological classes (there are also a few other classes):
* {{nihongo|adjectival verbs|形容詞|keiyōshi|conventionally called "{{transliteration|ja|i}}-adjectives"}}– these have roots and conjugating stem forms, and are semantically and morphologically similar to [[stative verb]]s.
* {{nihongo|adjectival nouns|形容動詞|keiyōdōshi|lit. "adjectival verb", conventionally called "{{transliteration|ja|na}}-adjectives"}}– these are nouns that combine with the copula.

Unlike adjectives in languages like English, {{transliteration|ja|i}}-adjectives in Japanese inflect for aspect and mood, like verbs. Japanese adjectives do not have comparative or superlative inflections; comparatives and superlatives have to be marked periphrastically using adverbs like {{nihongo3|'more'||motto}} and {{nihongo3|'most'||ichiban}}.

Every adjective in Japanese can be used in an [[Adjective#Attributive adjective|attributive position]], and nearly every Japanese adjective can be used in a [[Adjective#Predicative adjective|predicative position]]. There are a few Japanese adjectives that cannot predicate, known as {{nihongo3|attributives|連体詞|rentaishi}}, which are derived from other word classes; examples include {{nihongo3|"big"|大きな|ōkina}}, {{nihongo3|"small"|小さな|chiisana}}, and {{nihongo3|"strange"|おかしな|okashina}} which are all stylistic {{transliteration|ja|na}}-type variants of normal {{transliteration|ja|i}}-type adjectives.

All {{transliteration|ja|i}}-adjectives except for {{nihongo3|good|いい|ii}} have regular conjugations, and {{transliteration|ja|ii}} is irregular only in the fact that it is a changed form of the regular adjective {{nihongo3||良い|yoi}} permissible in the terminal and attributive forms. For all other forms it reverts to {{transliteration|ja|yoi}}.

{| class="wikitable" style="text-align:center"
|+ Stem forms for adjectives
|-
!rowspan="2"|
! {{transliteration|ja|i}}-adjectives
! {{transliteration|ja|na}}-adjectives
|-
! {{nihongo||安・い|yasu.}}
! {{nihongo||静か-|shizuka-}}
|-
! {{nihongo|Irrealis form|未然形|mizenkei}}
| {{nihongo||安かろ|.karo}}
| {{nihongo||静かだろ|-daro}}
|-
! {{nihongo|Continuative form|連用形|ren'yōkei}}
| {{nihongo||安く|.ku}}
| {{nihongo||静かで|-de}}
|-
! {{nihongo|Terminal form¹|終止形|shūshikei}}
| {{nihongo||安い|.i}}
| {{nihongo||静かだ|-da}}
|-
! {{nihongo|Attributive form¹|連体形|rentaikei}}
| {{nihongo||安い|.i}}
| {{nihongo||静かな|-na}}/{{pb}}{{nihongo||静かなる|-naru}}
|-
! {{nihongo|Hypothetical form|仮定形|kateikei}}
| {{nihongo||安けれ|.kere}}
| {{nihongo||静かなら|-nara}}
|-
! {{nihongo|Imperative form²|命令形|meireikei}}
| {{nihongo||安かれ|.kare}}
| {{nihongo||静かなれ|-nare}}
|}

# The attributive and terminal forms were formerly {{nihongo||安き|.ki}} and {{nihongo||安し|.shi}}, respectively; in modern Japanese these are used productively for stylistic reasons only, although many [[set phrase]]s such as {{nihongo3|anonymous|名無し|nanashi}} and {{nihongo3|[general positive interjection]|よし|yoshi|sometimes written {{transliteration|ja|yosh}}}}, derive from them.
# The imperative form is extremely rare in modern Japanese, restricted to set patterns like {{nihongo3|'sooner or later'|遅かれ早かれ|osokare hayakare}}, where they are treated as adverbial phrases. It is impossible for an imperative form to be in a predicate position.

Common conjugations of adjectives are enumerated below. {{transliteration|ja|ii}} is not treated separately, because all conjugation forms are identical to those of {{transliteration|ja|yoi}}.

{| class="wikitable" style="text-align:center"
|-
! &nbsp;
!colspan="2"| {{transliteration|ja|i}}-adjectives{{pb}}{{nihongo3|"cheap"|[[wikt:安い|安い]]|yasui}}
!colspan="2"| {{transliteration|ja|na}}-adjectives{{pb}}{{nihongo3|"quiet"|[[wikt:静か|静か]]|shizuka}}
|-
! informal nonpast
| root + {{transliteration|ja|-i}}{{pb}}(Used alone, without the copula)
| {{nihongo3|"is cheap"|安い|yasui}}
| root + copula {{transliteration|ja|da}}
| {{nihongo3|"is quiet"|静かだ|shizuka da}}
|-
! informal past
| cont. + {{nihongo||あった|atta}}{{pb}}({{transliteration|ja|u}} + {{transliteration|ja|a}} collapse)
| {{nihongo3|"was cheap"|安かった |yasuk.atta}}
| cont. + {{nihongo||あった|atta}}{{pb}}({{transliteration|ja|e}} + {{transliteration|ja|a}} collapse)
| {{nihongo3|"was quiet"|静かだった |shizuka d.atta}}
|-
! informal negative nonpast
| cont. + {{nihongo||(は)ない|(wa) nai}}¹
| {{nihongo3|"isn't cheap"|安く(は)ない|yasuku(wa)nai}}
| cont. + {{nihongo||(は)ない|(wa) nai}}
| {{nihongo3|"isn't quiet"|静かで(は)ない|shizuka de (wa) nai}}
|-
! informal negative past
| cont. + {{nihongo||(は)なかった|(wa) nakatta}}¹
| {{nihongo3|"wasn't cheap"|安く(は)なかった|yasuku(wa)nakatta}}
| cont. + {{nihongo||(は)なかった|(wa) nakatta}}
| {{nihongo3|"wasn't quiet"|静かで(は)なかった|shizuka de (wa) nakatta}}
|-
! polite nonpast
| root + {{transliteration|ja|-i}} + copula {{nihongo||です|desu}}
| {{nihongo3|"is cheap"|安いです|yasui desu}}
| root + copula {{nihongo||です|desu}}
| {{nihongo3|"is quiet"|静かです|shizuka desu}}
|-
!rowspan="2"| polite negative nonpast
| inf. cont + | {{nihongo||ありません|arimasen}}¹
| {{nihongo||安くありません|yasuku arimasen}}
| inf. cont + {{nihongo||(は)ありません|(wa) arimasen}}
| {{nihongo||静かではありません|shizuka de wa arimasen}}
|-
| inf. neg. non-past + copula {{nihongo||です|desu}}¹
| {{nihongo||安くないです|yasukunai desu}}
| inf. cont + {{nihongo||(は)ないです|(wa) nai desu}}
| {{nihongo||静かではないです|shizuka de wa nai desu}}
|-
!rowspan="2"| polite negative past
| inf. cont + {{nihongo||ありませんでした|arimasen　deshita}}
| {{nihongo||安くありませんでした|yasuku arimasen deshita}}
| inf. cont + {{nihongo||(は)ありませんでした|(wa) arimasen deshita}}
| {{nihongo||静かではありませんでした|shizuka de wa arimasen deshita}}
|-
| inf. neg. past + copula {{nihongo||です|desu}}¹
| {{nihongo||安くなかったです|yasukunakatta desu}}
| inf. neg. past + {{nihongo||なかったです|nakatta desu}}¹
| {{nihongo||静かではなかったです|shizuka de wa nakatta desu}}
|-
! {{transliteration|ja|-te}} form
| cont. + {{nihongo||て|te}}
| {{nihongo||安くて|yasuku.te}}
| cont.
| {{nihongo||静かで|shizuka de}}
|-
! provisional conditional
| hyp. + {{nihongo||ば|ba}}
| {{nihongo||安ければ|yasukere.ba}}
| hyp. (+ {{nihongo||ば|ba}})
| {{nihongo||静かなら(ば)|shizuka nara(ba)}}
|-
! past conditional
| inf. past + {{nihongo||ら|ra}}
| {{nihongo||安かったら |yasukatta.ra}}
| inf. past + {{nihongo||ら|ra}}
| {{nihongo||静かだったら |shizuka datta.ra}}
|-
! volitional²
| irrealis + {{nihongo||う|u}}
/root + {{nihongo||だろう|darō}}
| {{nihongo||安かろう|yasukarō}}
/ {{nihongo||安いだろう|yasuidarō}}
| irrealis + {{nihongo||う|u}}{{pb}}= root + {{nihongo||だろう|darō}}
| {{nihongo||静かだろう|shizuka darō}}
|-
! adverbial
| cont.
| {{nihongo||安く|yasuku.}}
| root + {{nihongo||に|ni}}
| {{nihongo||静かに|shizuka ni}}
|-
! degree {{nowrap|(-ness)}}
| root + {{nihongo||さ|sa}}
| {{nihongo||安さ|yasu-sa}}
| root + {{nihongo||さ|sa}}
| {{nihongo||静かさ|shizuka-sa}}
|}

# Note that these are just forms of the {{transliteration|ja|i}}-type adjective {{nihongo||ない|nai}}
# Since most adjectives describe non-volitional conditions, the volitional form is interpreted as "it is possible", if sensible. In some rare cases it is semi-volitional: {{nihongo3|'OK'|良かろう|yokarō|lit: "let it be good"}} in response to a report or request.

Adjectives too are governed by euphonic rules in certain cases, as noted in the section on it below. For the polite negatives of {{transliteration|ja|na}}-type adjectives, see also the section below on the copula {{nihongo||だ|da}}.

===Copula ({{lang|ja|だ}} {{transliteration|ja|da}})===
The [[Copula (linguistics)|copula]] {{transliteration|ja|da}} behaves very much like a verb or an adjective in terms of conjugation.

{| class="wikitable" style="text-align:center;"
|+ Stem forms of the copula
|-
! {{nihongo|Irrealis form|未然形|mizenkei}}
| {{nihongo||では|de wa}}
|-
! {{nihongo|Continuative form|連用形|ren'yōkei}}
| {{nihongo||で|de}}
|-
! {{nihongo|Terminal form|終止形|shūshikei}}
| {{nihongo||だ|da|informal}}{{pb}}{{nihongo||です|desu|polite}}{{pb}}{{nihongo||でございます|de gozaimasu|respectful}}
|-
! {{nihongo|Attributive form|連体形|rentaikei}}
| {{nihongo||である|de aru}}
|-
! {{nihongo|Hypothetical form|仮定形|kateikei}}
| {{nihongo||なら|nara}}
|-
! {{nihongo|Imperative form|命令形|meireikei}}
| {{nihongo||であれ|deare}}
|}

Note that there are no potential, causative, or passive forms of the copula, just as with adjectives.

The following are some examples.
<!-- The following needs placing into the template {{tl|Interlinear}}:-->
{{blockquote|{{lang|ja|ジョンは学生'''だ'''。}}
{{transliteration|ja|JON wa gakusei '''da'''}}
"John '''is''' a student."}}

{{blockquote|{{lang|ja|明日も晴れ'''なら'''、ピクニックしよう。}}
{{transliteration|ja|Ashita mo hare '''nara''', PIKUNIKKU shiyō}}
"'''If''' tomorrow '''is''' clear too, let's have a picnic."}}

In continuative conjugations, {{nihongo||では|de wa}} is often contracted in speech to {{nihongo||じゃ|ja}}; for some kinds of informal speech {{transliteration|ja|ja}} is preferable to {{transliteration|ja|de wa}}, or is the only possibility.

{| class="wikitable" style="float:none; text-align:center;"
|+ Conjugations of the copula
|-
!rowspan="3"| nonpast
! informal
| {{nihongo||だ|da}}
|-
! polite
| {{nihongo||です|desu}}
|-
! respectful
| {{nihongo||でございます|de gozaimasu}}
|-
!rowspan="3"| past
! informal
| cont. + {{nihongo||あった|atta}}{{pb}}{{nihongo||だった|datta}}
|-
! polite
| {{nihongo||でした|deshita}}
|-
! respectful
| {{nihongo||でございました|de gozaimashita}}
|-
!rowspan="3"| negative nonpast
! informal
| cont. + {{nihongo||はない|wa nai}}
| {{nihongo||じゃない|ja nai}}
|-
! polite
| cont. + {{nihongo||はありません|wa arimasen}}
| {{nihongo||じゃありません||ja arimasen}}
|-
! respectful
| cont. + {{nihongo||はございません|wa gozaimasen}}
| {{nihongo||じゃございません||ja gozaimasen}}
|-
!rowspan="3"| negative past
! informal
| cont. + {{nihongo||はなかった|wa nakatta}}
| {{nihongo||じゃなかった|ja nakatta}}
|-
! polite
| cont. + {{nihongo||はありませんでした|wa arimasen deshita}}
| {{nihongo||じゃありませんでした|ja arimasen deshita}}
|-
! respectful
| cont. + {{nihongo||はございませんでした|wa gozaimasen deshita}}
| {{nihongo||じゃございませんでした|ja gozaimasen deshita}}
|-
!rowspan="3"| conditional
! informal
| hyp. + {{nihongo||ば|ba}}
|-
! polite
|rowspan="2"| cont. + {{nihongo||あれば|areba}}
|-
! respectful
|-
!rowspan="3"| provisional
! informal
| {{nihongo||なら|nara}}
|-
! polite
|rowspan="2"| same as conditional
|-
! respectful
|-
!rowspan="3"| volitional
! informal
| {{nihongo||だろう|darō}}
|-
! polite
| {{nihongo||でしょう|deshō}}
|-
! respectful
| {{nihongo||でございましょう|de gozaimashō}}
|-
!rowspan="3"| adverbial and {{transliteration|ja|-te}} forms
! informal
| cont.
|-
! polite
| cont. + {{nihongo||ありまして|arimashite}}
|-
! respectful
| cont. + {{nihongo||ございまして|gozaimashite}}
|}

{{Clear}}

==={{nihongo|Euphonic changes|音便|onbin}}===
{{Main|Onbin}}

====Historical sound change====
<div style="float:right; margin-left:2em;">
{| class="wikitable"
|+ Spelling changes
! Archaic !! Modern
|-
| {{nihongo||あ＋う|a + u}}{{pb}}{{nihongo||あ＋ふ|a + fu}} || {{nihongo||おう|ō}}
|-
| {{nihongo||い＋う|i + u}}{{pb}}{{nihongo||い＋ふ|i + fu}} || {{nihongo||ゆう|yū}}<sup>1</sup>
|-
| {{nihongo||う＋ふ|u + fu}} || {{nihongo||うう|ū}}
|-
| {{nihongo||え＋う|e + u}}{{pb}}{{nihongo||え＋ふ|e + fu}} || {{nihongo||よう|yō}}
|-
| {{nihongo||お＋ふ|o + fu}} || {{nihongo||おう|ō}}
|-
| {{nihongo||お＋ほ|o + ho}}{{pb}}{{nihongo||お＋を|o + wo}} || {{nihongo||おお|ō}}
|-
| auxiliary verb {{nihongo||む|mu}} || {{nihongo||ん|n}}
|-
| medial or final {{nihongo||は|ha}} || {{nihongo||わ|wa}}
|-
| medial or final {{nihongo||ひ|hi}}, {{nihongo||へ|he}}, {{nihongo||ほ|ho}} || {{nihongo||い|i}}, {{nihongo||え|e}}, {{nihongo||お|o}}{{pb}}(via {{transliteration|ja|wi}}, {{transliteration|ja|we}}, {{transliteration|ja|wo}}, see below)
|-
| any {{nihongo||ゐ|wi}}, {{nihongo||ゑ|we}}, {{nihongo||を|wo}} || {{nihongo||い|i}}, {{nihongo||え|e}}, {{nihongo||お|o}}<sup>1</sup>
|}

# Usually not reflected in spelling
</div>

Modern pronunciation is a result of a long history of phonemic drift that can be traced back to written records of the 13th century, and possibly earlier. However, it was only in 1946 that the Japanese ministry of education modified existing [[kana]] usage to conform to the {{nihongo|standard dialect|共通語|kyōtsūgo}}. All earlier texts used the archaic orthography, now referred to as [[historical kana usage]]. The adjoining table is a nearly exhaustive list of these spelling changes.

Note that the palatalized morae {{lang|ja|ゆ}} and {{lang|ja|よ}} ({{transliteration|ja|yu}} and {{transliteration|ja|yo}}) combine with the initial consonant (if present) yielding a palatalized syllable. The most basic example of this is modern {{Nihongo3|today|今日（きょう）|kyō}}, which historically developed as {{Nihongo3||けふ|kefu}} → {{Nihongo3||きょう|kyō}}, via the {{Nihongo3||えふ|efu}} → {{Nihongo3||よう|yō}} rule.

A few sound changes are not reflected in the spelling. Firstly, {{transliteration|ja|ou}} merged with {{transliteration|ja|oo}}, both being pronounced as a long {{transliteration|ja|ō}}. Secondly, the particles {{lang|ja|は}} and {{lang|ja|を}} are still written using historical kana usage, though these are pronounced as {{transliteration|ja|wa}} and {{transliteration|ja|o}} respectively, rather than {{transliteration|ja|ha}} and {{transliteration|ja|wo}}.

Among Japanese speakers, it is not generally understood that the historical kana spellings were, at one point, reflective of pronunciation.{{Citation needed|date=November 2022}} For example, the modern {{transliteration|ja|on'yomi}} reading {{Nihongo3||よう|yō}} (for {{Nihongo|leaf|葉|yō}}) arose from the historical {{Nihongo3||えふ|efu}}. The latter was pronounced something like {{IPA|[ʲepu]}} by the Japanese at the time it was borrowed (compare [[Middle Chinese]] {{IPA|[jiɛp̚]}}). However, a modern reader of a classical text would still read this as {{IPAc-ja|yō}}, the modern pronunciation.

====Verb conjugations====
{{Main|Japanese verb conjugation}}

Conjugations of some verbs and adjectives differ from the prescribed formation rules because of euphonic changes. Nearly all of these euphonic changes are themselves regular. For verbs the exceptions are all in the ending of the continuative form of group when the following auxiliary starts with a {{transliteration|ja|t}}-sound (i.e. {{nihongo||-た|-ta}}, {{nihongo||-て|-te}}, {{nihongo||-たり|-tari}}, etc.).

{{clear}}

{| class="wikitable"
! Continuative ending !! Changes to !! Example
|-
| {{nihongo||い|i}}, {{nihongo||ち|chi}} or {{nihongo||り|ri}}
| {{lang|ja|っ}} ([[Gemination#Japanese|double consonant]], [[sokuon]], [[sokuonbin]])
| {{nihongo||＊買いて|*kaite}} → {{nihongo||買って|katte}}{{pb}}{{nihongo||＊打ちて|*uchite}} → {{nihongo||打って|utte}}{{pb}}{{nihongo||＊知りて|*shirite}} → {{nihongo||知って|shitte}}
|-
| {{nihongo||び|bi}}, {{nihongo||み|mi}} or {{nihongo||に|ni}}
| {{nihongo|syllabic {{transliteration|ja|n}}|ん}} ([[Japanese phonology#Moraic consonants|hatsuon]], [[hatsuonbin]]), with the following {{nihongo||タ|t}} sound [[consonant voicing|voiced]]
| {{nihongo||＊遊びて|*asobite}} → {{nihongo||遊んで|asonde}}{{pb}}{{nihongo||＊住みて|*sumite}} → {{nihongo||住んで|sunde}}{{pb}}{{nihongo||＊死にて|*shinite}} → {{nihongo||死んで|shinde}}
|-
| {{nihongo||き|ki}}
| {{nihongo||い|i}} ([[i-onbin]])
| {{nihongo||＊書きて|*kakite}} → {{nihongo||書いて|kaite}}
|-
| {{nihongo||ぎ|gi}}
| {{nihongo||い|i}}, with the following {{nihongo||タ|t}} sound voiced
| {{nihongo||＊泳ぎて|*oyogite}} → {{nihongo||泳いで|oyoide}}
|}

<nowiki>*</nowiki> denotes impossible/ungrammatical form.

There is one other irregular change: {{nihongo3|to go|行く|iku}}, for which there is an exceptional continuative form: {{nihongo||行き|iki}} + {{nihongo||て|te}} → {{nihongo||行って|itte}}, {{nihongo||行き|iki}} + {{nihongo||た|ta}} → {{nihongo||行った|itta}}, etc.

There are dialectical differences, which are also regular and generally occur in similar situations. For example, in [[Kansai dialect]] the {{transliteration|ja|-i}} + {{transliteration|ja|t-}} conjugations are instead changed to {{transliteration|ja|-ut-}} ([[u-onbin]]), as in {{Nihongo3||思うた|omōta}} instead of {{Nihongo3||思った|omotta}}, as perfective of {{Nihongo3|think|思う|omou}}. In this example, this can combine with the preceding vowel via historical sound changes, as in {{Nihongo3||しもうた|shimōta}} ({{transliteration|ja|au}} → {{transliteration|ja|ō}}) instead of standard {{Nihongo3||しまった|shimatta}}.

====Polite forms of adjectives====
The continuative form of proper adjectives, when followed by polite forms such as {{Nihongo3|be|ござる/御座る|gozaru}} or {{Nihongo3|know, think|存じる|zonjiru}}, undergoes a transformation; this may be followed by historical sound changes, yielding a one-step or two-step sound change. Note that these verbs are almost invariably conjugated to polite {{Nihongo3||〜ます|-masu}} form, as {{Nihongo3||ございます|gozaimasu}} and {{Nihongo3||存じます|zonjimasu}} (note the irregular conjugation of {{transliteration|ja|gozaru}}, discussed below), and that these verbs are preceded by the ''continuative'' form – {{Nihongo3||〜く|-ku}} – of adjectives, rather than the terminal form – {{Nihongo3||〜い|-i}} – which is used before the more everyday {{Nihongo3|be|です|desu}}.

The rule is {{Nihongo3||〜く|-ku}} → {{Nihongo3||〜う|-u}} (dropping the {{transliteration|ja|-k-}}), possibly also combining with the previous syllable according to the spelling reform chart, which may also undergo palatalization in the case of {{Nihongo3||ゆ、よ|yu, yo}}.

Historically there were two classes of proper [[Old Japanese#Adjectives|Old Japanese adjectives]], {{Nihongo3||〜く|-ku}} and {{Nihongo3||〜しく|-shiku}} ("{{transliteration|ja|-ku}} adjective" means "not preceded by {{transliteration|ja|shi}}"). This distinction collapsed during the evolution of [[Late Middle Japanese#Adjectives|Late Middle Japanese adjectives]], and both are now considered {{Nihongo3||〜い|-i}} adjectives. The sound change for {{transliteration|ja|-shii}} adjectives follows the same rule as for other {{transliteration|ja|-ii}} adjectives, notably that the preceding vowel also changes and the preceding mora undergoes palatalization, yielding {{Nihongo3||〜しく|-shiku}} → {{Nihongo3||〜しゅう|-shū}}, though historically this was considered a separate but parallel rule.

{| class=wikitable
! Continuative ending !! Changes to !! Example
|-
| {{nihongo||〜あく|-aku}}
| {{nihongo||〜おう|-ō}}
| {{nihongo||＊おはやくございます|*ohayaku gozaimasu}} →{{pb}}{{nihongo||おはようございます|ohayō gozaimasu}}
|-
| {{nihongo||〜いく|-iku}}
| {{nihongo||〜ゆう|-yū}}
| {{nihongo||＊大きくございます|*ōkiku gozaimasu}} →{{pb}}{{nihongo||大きゅうございます|ōkyū gozaimasu}}
|-
| {{nihongo||〜うく|-uku}}
| {{nihongo||〜うう|-ū}}
| {{nihongo||＊寒くございます|*samuku gozaimasu}} →{{pb}}{{nihongo||寒うございます|samū gozaimasu}}
|-
| {{nihongo||＊〜えく|*-eku}}
| {{nihongo||＊〜よう|*-yō}}
| (not present)
|-
| {{nihongo||〜おく|-oku}}
| {{nihongo||〜おう|-ō}}
| {{nihongo||＊面白くございます|*omoshiroku gozaimasu}} →{{pb}}{{nihongo||面白うございます|omoshirō gozaimasu}}
|-
| {{nihongo||〜しく|-shiku}}
| {{nihongo||〜しゅう|-shū}}
| {{nihongo||＊涼しくございます|*suzushiku gozaimasu}} →{{pb}}{{nihongo||涼しゅうございます|suzushū gozaimasu}}
|}

====Respectful verbs====
Respectful verbs such as {{nihongo3|'to get'|くださる|kudasaru}}, {{nihongo3|'to do'|なさる|nasaru}}, {{nihongo3|'to be'|ござる|gozaru}}, {{nihongo3|'to be/come/go'|いらっしゃる|irassharu}}, {{nihongo3|'to say'|おっしゃる|ossharu}}, etc. behave like group 1 verbs, except in the continuative and imperative forms.

{| class="wikitable"
! !! Change !! Example
|-
! continuative
| {{nihongo||〜り|-ri}} changed to {{nihongo||〜い|-i}} || {{nihongo||＊ござります|*gozarimasu}} → {{nihongo||ございます|gozaimasu}}{{pb}}{{nihongo||＊いらっしゃりませ|*irassharimase}} → {{nihongo||いらっしゃいませ|irasshaimase}}
|-
! imperative
| {{nihongo||〜れ|-re}} changed to {{nihongo||〜い|-i}} || {{nihongo||＊くだされ|*kudasare}} → {{nihongo||ください|kudasai}}{{pb}}{{nihongo||＊なされ|*nasare}} → {{nihongo||なさい|nasai}}
|}

====Colloquial contractions====
In speech, common combinations of conjugation and auxiliary verbs are contracted in a fairly regular manner.

{| class=wikitable
|+ Colloquial contractions
|-
! Full form || Colloquial !! Example
|-
| {{nihongo||〜てしまう|-te shimau}}
| {{nihongo||〜ちゃう/-ちまう|-chau/-chimau}}{{pb}}group 1
| {{fs interlinear|lang=ja
 | 負け'''て''' '''しまう''' → 負け'''ちゃう''' / 負け'''ちまう'''
 | make'''te''' '''shimau''' {} make'''chau''' / make'''chimau'''
 | 'lose'}}
|-
| {{nihongo||〜でしまう|-de shimau}}
| {{nihongo||〜じゃう/〜じまう|-jau/-jimau}}{{pb}}group 1
| {{fs interlinear|lang=ja
 | 死ん'''で''' '''しまう''' → 死ん'''じゃう''' / 死ん'''じまう'''
 | shin'''de''' '''shimau''' {} shin'''jau''' / shin'''jimau'''
 | 'die'}}
|-
| {{nihongo||〜ては|-te wa}}
| {{nihongo||〜ちゃ|-cha}}
| {{fs interlinear|lang=ja
 | 食べ'''て''' '''は''' いけない → 食べ'''ちゃ''' いけない
 | tabe'''te''' '''wa''' ikenai {} tabe'''cha''' ikenai
 | 'must not eat'}}
|-
| {{nihongo||〜では|-de wa}}
| {{nihongo||〜じゃ|-ja}}
| {{fs interlinear|lang=ja
 | 飲ん'''で''' '''は''' いけない → 飲ん'''じゃ''' いけない
 | non'''de''' '''wa''' ikenai {} non'''ja''' ikenai
 | 'must not drink'}}
|-
| {{nihongo||〜ている|-te iru}}
| {{nihongo||〜てる|-teru}}{{pb}}group 2b
| {{fs interlinear|lang=ja
 | 寝'''て''' '''いる''' → 寝'''てる'''
 | ne'''te''' '''iru''' {} ne'''teru'''
 | 'is sleeping'}}
|-
| {{nihongo||〜ておく|-te oku}}
| {{nihongo||〜とく|-toku}}{{pb}}group 1
| {{fs interlinear|lang=ja
 | し'''て''' '''おく''' → し'''とく'''
 | shi'''te''' '''oku''' {} shi'''toku'''
 | 'will do it so'}}
|-
| {{nihongo||〜て行く|-te iku}}
| {{nihongo||〜てく|-teku}}{{pb}}group 1
| {{fs interlinear|lang=ja
 | 出'''て''' '''行け''' → 出'''てけ'''
 | de'''te''' '''ike''' {} de'''teke'''
 | 'get out!'}}
|-
| {{nihongo||〜てあげる|-te ageru}}
| {{nihongo||〜たげる|-tageru}}{{pb}}group 2a
| {{fs interlinear|lang=ja
 | 買っ'''て''' '''あげる''' → 買っ'''たげる'''
 | kat'''te''' '''ageru''' {} kat'''tageru'''
 | 'buy something (for someone)'}}
|-
| {{nihongo||〜るの|-ru no}}
| {{nihongo||〜んの|-nno}}
| {{fs interlinear|lang=ja
 | 何 して い'''る''' '''の''' → 何 して'''んの'''
 | nani shite i'''ru''' '''no''' {} nani shite'''nno'''
 | 'what are you doing?'}}
|-
| {{nihongo||〜りなさい|-rinasai}}
| {{nihongo||〜んなさい|-nnasai}}
| {{fs interlinear|lang=ja
 | や'''りなさい''' → や'''んなさい'''
 | ya'''rinasai''' {} ya'''nnasai'''
 | 'do it!'}}
|-
| {{nihongo||〜るな|-runa}}
| {{nihongo||〜んな|-nna}}
| {{fs interlinear|lang=ja
 | や'''るな''' → や'''んな'''
 | ya'''runa''' {} ya'''nna'''
 | 'don't do it!'}}
|-
| {{nihongo||〜れは or 〜れば|-re wa or -reba}}
| {{nihongo||〜りゃ|-rya}}
| {{fs interlinear|lang=ja
 | どう す'''れば''' いい の だろう → どう す'''りゃ'''(あ） いいん だろう
 | dou su'''reba''' ii no darou {} dou su'''rya''' iin darou
 | 'what should I do?'}}
|}

There are occasional others, such as {{transliteration|ja|-aranai}} → {{transliteration|ja|-annai}} as in {{Nihongo3|don't understand|分からない|wakaranai}} → {{Nihongo3||分かんない|wakannai}} and {{Nihongo3|boring|つまらない|tsumaranai}} → {{Nihongo3||つまんない|tsumannai}} – these are considered quite casual and are more common among the younger generation.{{Citation needed|date=November 2021}}

Contractions differ by dialect, but behave similarly to the standard ones given above. For example, in the [[Kansai dialect]], {{Nihongo3||〜てしまう|-te shimau}} → {{Nihongo3||〜てまう|-temau}}.