Japanese grammar

The modern theory of constituent order ("word order"), usually attributed to Joseph Greenberg, identifies several kinds of phrases. Each one has a head and possibly a modifier. The head of a phrase either precedes its modifier (head initial) or follows it (head final). Some of these phrase types, with the head marked in boldface, are:

• genitive phrase, i.e., noun modified by another noun ("the cover of the book", "the book's cover");
• noun governed by an adposition ("on the table", "underneath the table");
• comparison ("[X is] bigger than Y", i.e., "compared to Y, X is big").
• noun modified by an adjective ("black cat").

Some languages are inconsistent in constituent order, having a mixture of head initial phrase types and head final phrase types. Looking at the preceding list, English for example is mostly head initial, but nouns follow the adjectives which modify them. Moreover, genitive phrases can be either head initial or head final in English. Japanese, by contrast, is the epitome of a head final language:

• genitive phrase: "猫の色" (neko no iro), cat GEN color = "the cat's (neko no) color (iro)";
• noun governed by an adposition:日本に (nihon ni), Japan in = "in Japan";
• comparison: "Yより大きい" (Y yori ookii), Y than big = "bigger than Y";
• noun modified by an adjective: "黒い猫" (kuroi neko) = "black cat".

Head finality in Japanese sentence structure carries over to the building of sentences using other sentences. In sentences that have other sentences as constituents, the subordinated sentences (relative clauses, for example), always precede what they refer to, since they are modifiers and what they modify has the syntactic status of phrasal head. Translating the phrase the man who was walking down the street into Japanese word order would be street down walking was man. (Note that Japanese has no articles, and the different word order obviates any need for the relative pronoun who.)

Head finality prevails also when sentences are coordinated instead of subordinated. In the world's languages, it is common to avoid repetition between coordinated clauses by optionally deleting a constituent common to the two parts, as in Bob bought his mother some flowers and his father a tie, where the second bought is omitted. In Japanese, such "gapping" must precede in the reverse order: Bob mother for some flowers and father for tie bought. The reason for this is that in Japanese, sentences (other than occasional inverted sentences or sentences containing afterthoughts) always end in a verb (or other predicative words like adjectival verbs, adjectival nouns, auxiliary verbs)—the only exceptions being a few sentence-ending particles such as ka, ne, and yo. The particle ka turns a statement into a question, while the others express the speaker's attitude towards the statement.

Japanese has five major lexical word classes:

• nouns
• verbal nouns (correspond to English gerunds like 'studying', 'jumping', which denote activities)
• nominal adjectives (names vary, also called na-adjectives or "adjectival nouns")
• verbs
• adjectives (so-called i-adjectives)

More broadly, there are two classes: uninflectable (nouns, including verbal nouns and adjectival nouns) and inflectable (verbs, with adjectives as defective verbs). To be precise, a verbal noun is simply a noun to which suru (する, "do") can be appended, while an adjectival noun is like a noun but uses -na (〜な) instead of -no (〜の) when acting attributively. Adjectives (i-adjectives) inflect identically to the negative form of verbs, which end in na-i (ない). Compare tabe-na-i (食べない, don't eat) → tabe-na-katta (食べなかった, didn't eat) and atsu-i (熱い, is hot) → atsu-katta (熱かった, was hot).

Some scholars, such as Eleanor Harz Jorden, refer to adjectives instead as adjectivals, since they are grammatically distinct from adjectives: they can predicate a sentence. That is, atsui (熱い) is glossed as "hot" when modifying a noun phrase, as in atsui gohan (熱いご飯, hot food), but as "is hot" when predicating, as in gohan wa atsui (ご飯は熱い, [the] food is hot).

The two inflected classes, verb and adjective, are closed classes, meaning they do not readily gain new members.[2][3] Instead, new and borrowed verbs and adjectives are conjugated periphrastically as verbal noun + suru (e.g. benkyō suru (勉強する, do studying; study)) and adjectival noun + na. This differs from Indo-European languages, where verbs and adjectives are open classes, though analogous "do" constructions exist, including English "do a favor", "do the twist" or French "faire un footing" (do a "footing", go for a jog), and periphrastic constructions are common for other senses, like "try climbing" (verbal noun) or "try parkour" (noun). Other languages where verbs are a closed class include Basque: new Basque verbs are only formed periphrastically. Conversely, pronouns are closed classes in Western languages but open classes in Japanese and some other East Asian languages.

In a few cases new verbs are created by appending -ru (〜る) to a noun or using it to replace the end of a word. This is most often done with borrowed words, and results in a word written in a mixture of katakana (stem) and hiragana (inflectional ending), which is otherwise very rare.[4] This is typically casual, with the most well-established example being sabo-ru (サボる, cut class; play hooky) (circa 1920), from sabotāju (サボタージュ, sabotage), with other common examples including memo-ru (メモる, write a memo), from memo (メモ, memo), and misu-ru (ミスる, make a mistake) from misu (ミス, mistake). In cases where the borrowed word already ends with a ru (ル), this may be punned to a ru (る), as in gugu-ru (ググる, to google), from Google (グーグル), and dabu-ru (ダブる, to double), from daburu (ダブル, double).[5]

New adjectives are extremely rare; one example is kiiro-i (黄色い, yellow), from adjectival noun kiiro (黄色), and a more casual recent example is kimo-i (きもい, gross), by contraction of kimochi waru-i (気持ち悪い, bad-feeling).[6] By contrast, in Old Japanese -shiki (〜しき) adjectives (precursors of present i-adjectives ending in -shi-i (〜しい), formerly a different word class) were open, as reflected in words like ita-ita-shi-i (痛々しい, pitiful), from the adjective ita-i (痛い, painful, hurt), and kō-gō-shi-i (神々しい, heavenly, sublime), from the noun kami (神, god) (with sound change). Japanese adjectives are unusual in being closed class but quite numerous – about 700 adjectives – while most languages with closed class adjectives have very few.[7][8] Some believe this is due to a grammatical change of inflection from an aspect system to a tense system, with adjectives predating the change.

The conjugation of i-adjectives has similarities to the conjugation of verbs, unlike Western languages where inflection of adjectives, where it exists, is more likely to have similarities to the declension of nouns. Verbs and adjectives being closely related is unusual from the perspective of English, but is a common case across languages generally, and one may consider Japanese adjectives as a kind of stative verb.

Japanese vocabulary has a large layer of Chinese loanwords, nearly all of which go back more than one thousand years, yet virtually none of them are verbs or "i-adjectives" – they are all nouns, of which some are verbal nouns (suru) and some are adjectival nouns (na). In addition to the basic verbal noun + suru form, verbal nouns with a single-character root often experienced sound changes, such as -suru (〜する) → -zuru (〜ずる) → -jiru (〜じる), as in kin-jiru (禁じる, forbid), and some cases where the stem underwent sound change, as in tassuru (達する, reach), from tatsu (達).

Verbal nouns are uncontroversially nouns, having only minor syntactic differences to distinguish them from pure nouns like 'mountain'. There are some minor distinctions within verbal nouns, most notably that some primarily conjugate as -o suru (〜をする) (with a particle), more like nouns, while others primarily conjugate as -suru (〜する), and others are common either way. For example, keiken o suru (経験をする, to experience) is much more common than keiken suru (経験する), while kanben suru (勘弁する, to pardon) is much more common than kanben o suru (勘弁をする).[9] Nominal adjectives have more syntactic differences versus pure nouns, and traditionally were considered more separate, but they, too, are ultimately a subcategory of nouns.

There are a few minor word classes that are related to adjectival nouns, namely the taru adjectives and naru adjectives. Of these, naru adjectives are fossils of earlier forms of na adjectives (the nari adjectives of Old Japanese), and are typically classed separately, while taru adjectives are a parallel class (formerly tari adjectives in Late Old Japanese), but are typically classed with na adjectives.

In discourse pragmatics, the term topic refers to what a section of discourse is about. At the beginning of a section of discourse, the topic is usually unknown, in which case it is usually necessary to explicitly mention it. As the discourse carries on, the topic need not be the grammatical subject of each new sentence.

Starting with Middle Japanese, the grammar evolved so as to explicitly distinguish topics from nontopics. This is done by two distinct particles (short words which do not change form). Consider the following pair of sentences:

太陽が昇る。

taiyō ga noboru

sun NONTOPIC rise

太陽は昇る。

taiyō wa noboru

sun TOPIC rise

Both sentences translate as "the sun rises". In the first sentence the sun (太陽 taiyō) is not a discourse topic—not yet; in the second sentence it now is a discourse topic. In linguistics (specifically, in discourse pragmatics) a sentence such as the second one (with wa) is termed a presentational sentence because its function in the discourse is to present sun as a topic, to "broach it for discussion". Once a referent has been established as the topic of the current monolog or dialog, then in (formal) modern Japanese its marking will change from ga to wa. To better explain the difference, the translation of the second sentence can be enlarged to "As for the sun, it rises" or "Speaking of the sun, it rises"; these renderings reflect a discourse fragment in which "the sun" is being established as the topic of an extended discussion.

The grammatical subject is commonly omitted in Japanese, as in

日本に行きました

nihon ni ikimashita

Japan LOCATIVE go-POLITE-PERFECTIVE

The sentence literally expresses "went to Japan". Subjects are mentioned when a topic is introduced, or in situations where an ambiguity might result from their omission. The preceding example sentence would most likely be uttered in the middle of a discourse, where who it is that "went to Japan" will be clear from what has already been said (or written).

In Japanese, phrasal constituents can be moved to the beginning or the end of the sentence. Leftward movement of a phrasal constituent is referred to as "scrambling".

Uehara (1998)[10] observes that Japanese grammarians have disagreed as to the criteria that make some words "inflectional", katsuyō, and others not, in particular, the 形容動詞 keiyōdōshi – "na-adjectives" or "na-nominals". (It is not disputed that nouns like 'book' and 'mountain' are noninflectional and that verbs and i-adjectives are inflectional.) The claim that na-adjectives are inflectional rests on the claim that the syllable da 'is', usually regarded as a "copula verb", is really a suffix—an inflection. Thus hon 'book', generates a one-word sentence, honda 'it is a book', not a two-word sentence, hon da. However, numerous constructions seem to be incompatible with the suffixal copula claim.

(1) Reduplication for emphasis

Hora! Hon, hon! 'See, it is a book!'

Hora! Kirei, kirei! 'See, it is pretty!'

Hora! Furui, furui! 'See, it is old!' (the adjectival inflection -i cannot be left off)

Hora! Iku, iku! 'See, it does go!' (the verbal inflection -u cannot be left off)

(2) Questions. In Japanese, questions are formed by adding the particle ka (or in colloquial speech, just by changing the intonation of the sentence).

Hon/kirei ka? 'Is it a book? ; Is it pretty?'

Furu-i/Ik-u ka? 'Is it old? ; Does it go?' (the inflections cannot be left off)

(3) Several auxiliary verbs, e.g., mitai, 'looks like it's'

Hon mitai da; Kirei mitai da 'It seems to be a book; It seems to be pretty'

Furu-i mitai da; Ik-u mitai da 'It seems to be old; It seems to go'

On the basis of such constructions, Uehara (1998) finds that the copula is indeed an independent word, and that regarding the parameters on which i-adjectives share the syntactic pattern of verbs, the nominal adjectives pattern with pure nouns instead.

Similarly, Eleanor Jorden considers this class of words a kind of nominal, not adjective, and refers to them as na-nominals in her textbook Japanese: The Spoken Language.

Grammatical cases in Japanese are marked by particles placed after the nouns.[11] A distinctive feature of Japanese is the presence of two cases which are roughly equivalent to the nominative case in other languages: one representing the sentence topic, other representing the subject. The most important case markers are the following:

• Nominative – が (ga) for subject, は (wa) for the topic
• Genitive – の (no)
• Dative – に (ni)
• Accusative – を (o)
• Lative – へ (e), used for destination direction (like in "to some place")
• Ablative – から (kara), used for source direction (like in "from some place")
• Instrumental – で (de)

Although many grammars and textbooks mention pronouns (代名詞 daimeishi), Japanese lacks true pronouns. (Daimeishi can be considered a subset of nouns.) Strictly speaking, pronouns do not take modifiers, but Japanese daimeishi do: 背の高い彼 se no takai kare (lit. tall he) is valid in Japanese. Also, unlike true pronouns, Japanese daimeishi are not closed-class: new daimeishi are introduced and old ones go out of use relatively quickly.

A large number of daimeishi referring to people are translated as pronouns in their most common uses. Examples: 彼 kare, (he); 彼女 kanojo, (she); 私 watashi, (I); see also the adjoining table or a longer list.[12] Some of these "personal nouns" such as 己 onore, I (exceedingly humble), or 僕 boku, I (young male), also have second-person uses: おのれ onore in second-person is an extremely rude "you", and boku in second-person is a diminutive "you" used for young boys. Kare and kanojo also mean "boyfriend" and "girlfriend" respectively, and this usage of the words is possibly more common than the use as pronouns.

Like other subjects, Japanese deemphasizes personal daimeishi, which are seldom used. This is partly because Japanese sentences do not always require explicit subjects, and partly because names or titles are often used where pronouns would appear in a translation:

「木下さんは、背が高いですね。」

Kinoshita-san wa, se ga takai desu ne.

(addressing Mr. Kinoshita) "You're pretty tall, aren't you?"

「専務、明日福岡市西区の山本商事の社長に会っていただけますか？」

Senmu, asu Fukuoka-shi nishi-ku no Yamamoto-shōji no shachō ni atte itadakemasu ka?

(addressing the managing director) "Would it be possible for you to meet the president of Yamamoto Trading Co. in West Ward, Fukuoka tomorrow?"

The possible referents of daimeishi are sometimes constrained depending on the order of occurrence. The following pair of examples from Bart Mathias[13] illustrates one such constraint.

Honda-kun ni atte, kare no hon o kaeshita (本田君に会って、彼の本を返した。)

(I) met Honda and returned his book. ("His" here can refer to Honda.)

Kare ni atte, Honda-kun no hon o kaeshita (彼に会って、本田君の本を返した。)

(I) met him and returned Honda's book. (Here, "him" cannot refer to Honda.)

English has a reflexive form of each personal pronoun (himself, herself, itself, themselves, etc.); Japanese, in contrast, has one main reflexive daimeishi, namely jibun (自分), which can also mean 'I'. The uses of the reflexive (pro)nouns in the two languages are very different, as demonstrated by the following literal translations (*=impossible, ??=ambiguous):

If the sentence has more than one grammatical or semantic subject, then the target of jibun is the subject of the primary or most prominent action; thus in the following sentence jibun refers unambiguously to Shizuko (even though Makoto is the grammatical subject) because the primary action is Shizuko's reading.

誠は静子に自分の家で本を読ませた。

Makoto wa Shizuko ni jibun no uchi de hon o yomaseta.

Makoto made Shizuko read book(s) in her house.

In practice the main action is not always discernible, in which case such sentences are ambiguous. The use of jibun in complex sentences follows non-trivial rules.

There are also equivalents to jibun such as mizukara. Other uses of the reflexive pronoun in English are covered by adverbs like hitorideni which is used in the sense of "by oneself". For example,

機械がひとりでに動き出した

kikai ga hitorideni ugokidashita

"The machine started operating by itself."

Change in a verb's valency is not accomplished by use of reflexive pronouns (in this Japanese is like English but unlike many other European languages). Instead, separate (but usually related) intransitive verbs and transitive verbs are used. There is no longer any productive morphology to derive transitive verbs from intransitive ones, or vice versa.

Demonstratives occur in the ko-, so-, and a- series. The ko- (proximal) series refers to things closer to the speaker than the hearer, the so- (medial) series for things closer to the hearer, and the a- (distal) series for things distant to both the speaker and the hearer. With do-, demonstratives turn into the corresponding interrogative form. Demonstratives can also be used to refer to people, for example

「こちらは林さんです。」

Kochira wa Hayashi-san desu.

"This is Mr. Hayashi."

Demonstratives limit, and therefore precede, nouns; thus この本 kono hon for "this/my book", and その本 sono hon for "that/your book".

When demonstratives are used to refer to things not visible to the speaker or the hearer, or to (abstract) concepts, they fulfill a related but different anaphoric role. The anaphoric distals are used for shared information between the speaker and the listener.

A：先日、札幌に行って来ました。

A: Senjitsu, Sapporo ni itte kimashita.

A: I visited Sapporo recently.

B：あそこ(*そこ)はいつ行ってもいい所ですね。

B: Asoko (*Soko) wa itsu itte mo ii tokoro desu ne.

B: Yeah, that's a great place to visit whenever you go.

Soko instead of asoko would imply that B doesn't share this knowledge about Sapporo, which is inconsistent with the meaning of the sentence. The anaphoric medials are used to refer to experience or knowledge that is not shared between the speaker and listener.

佐藤：田中という人が昨日死んだんだって。

Satō : Tanaka to iu hito ga kinō shinda n da tte...

Sato: I heard that a man called Tanaka died yesterday...

森：えっ、本当?

Mori: E', hontō?

Mori: Oh, really?

佐藤：だから、その(*あの)人、森さんの昔の隣人じゃなかったっけ？

Satō : Dakara, sono (*ano) hito, Mori-san no mukashi no rinjin ja nakatta 'kke?

Sato: It's why I asked... wasn't he an old neighbour of yours?

Again, ano is inappropriate here because Sato doesn't (didn't) know Tanaka personally. The proximal demonstratives do not have clear anaphoric uses. They can be used in situations where the distal series sound too disconnected:

一体何ですか、これ(*あれ)は?

Ittai nan desu ka, kore (*are) wa?

What on earth is this?

Prior to discussing the conjugable words, a brief note about stem forms. Conjugative suffixes and auxiliary verbs are attached to the stem forms of the affixee. In modern Japanese there are the following six stem forms.

Note that this order follows from the -a, -i, -u, -e, -o endings that these forms have in 五段 (5-row) verbs (according to the 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 na-nominals.

Irrealis form (未然形 mizenkei) -a (and -ō)

is used for plain negative (of verbs), causative and passive constructions. The most common use of this form is with the -nai auxiliary that turns verbs into their negative (predicate) form. (See Verbs below.) The -ō version is used for volitional expression and formed by a euphonic change (音便 onbin).

Continuative form (連用形 ren'yōkei) -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 -te ending. This form is also used to negate adjectives.

Terminal form (終止形 shūshikei) -u

is used at the ends of clauses in predicate positions. This form is also variously known as plain form (基本形 kihonkei) or dictionary form (辞書形 jishokei) – it is the form that verbs are listed under in a dictionary.

Attributive form (連体形 rentaikei) -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, na-nominals behave differently in terminal and attributive positions; see adjectives, below.

Hypothetical form (仮定形 kateikei) -e

is used for conditional and subjunctive forms, using the -ba ending.

Imperative form (命令形 meireikei) -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 euphonic principles (音便 onbin), which are discussed below.

Verbs (動詞 dōshi) in Japanese are rigidly constrained to the ends of clauses in what is known as the predicate position. This means that the verb is always located at the end of a sentence.

The subject and objects of the verb are indicated by means of particles, and the grammatical functions of the verb — primarily tense and voice — are indicated by means of 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 nonpast. 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, and the auxiliary verb iru "to be"; to illustrate, 見る miru ("to see") → 見ている mite iru ("to be seeing").

Verbs can be semantically classified based on certain conjugations.

Stative verbs

indicate existential properties, such as "to be" (いる iru), "to be able to do" (出来る dekiru), "to need" (要る iru), etc. These verbs generally do not have a continuative conjugation with -iru because they are semantically continuative already.

Continual verbs

conjugate with the auxiliary -iru to indicate the progressive aspect. Examples: "to eat" (食べる taberu), "to drink" (飲む nomu), "to think" (考える kangaeru). To illustrate the conjugation, 食べる taberu ("to eat") → 食べている tabete iru ("to be eating").

Punctual verbs

conjugate with -iru to indicate a repeated action, or a continuing state after some action. Example: 知る shiru ("to know") → 知っている shitte iru ("to be knowing"); 打つ utsu ("to hit") → 打っている utte iru ("to be hitting (repeatedly)").

Non-volitional verb

indicate uncontrollable action or emotion. These verbs generally have no volitional, imperative or potential conjugation. Examples: 好む konomu, "to like / to prefer" (emotive), 見える mieru, "to be visible" (non-emotive).

Movement verbs

indicate motion. Examples: 歩く aruku ("to walk"), 帰る kaeru ("to return"). In the continuative form (see below) they take the particle 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 consonant and vowel verbs).

Group 2a (上一段 kami ichidan, lit. upper 1-row group)

verbs with a stem ending in i. The terminal stem form always rhymes with -iru. Examples: 見る miru ("to see"), 着る kiru ("to wear").

Group 2b (下一段 shimo ichidan, lit. lower 1-row group)

verbs with a stem ending in e. The terminal stem form always rhymes with -eru. Examples: 食べる taberu ("to eat"), くれる kureru ("to give" (to someone of lower or more intimate status)). (Note that some Group 1 verbs resemble Group 2b verbs, but their stems end in r, not e.)

Group 1 (五段 godan, lit. 5-row group)

verbs with a stem ending in a consonant. When this is r and the verb ends in -eru, it is not apparent from the terminal form whether the verb is Group 1 or Group 2b, e.g. 帰る kaeru ("to return"). If the stem ends in w, that sound only appears in before the final 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 u-row) i.e. i-row. "Lower 1-row" means the row that is one row below the center row (the u-row) i.e. 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, 見る (miru, "to see") belongs to マ行上一段活用 (ma-column i-row conjugation), 食べる (taberu, "to eat") belongs to バ行下一段活用 (ba-column e-row conjugation), and 帰る (kaeru, "to return") belongs to ラ行五段活用(ra-column 5-row conjugation).

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

Historical note: classical Japanese had upper and lower 1- and 2-row groups and a 4-row group (上／下一段 kami/shimo ichidan, 上／下二段 kami/shimo nidan, and 四段 yodan, the nidan verbs becoming most of today's ichidan verbs (there were only a handful of kami ichidan verbs and only one single shimo ichidan verb in classical Japanese), and the yodan group, due to the writing reform in 1946 to write Japanese as it is pronounced, naturally became the modern godan verbs. Since verbs have migrated across groups in the history of the language, conjugation of classical verbs is not predictable from a knowledge of modern Japanese alone.

Of the irregular classes, there are two:

sa-group

which has only one member, する (suru, "to do"). In Japanese grammars these words are classified as サ変 sa-hen, an abbreviation of サ行変格活用 sa-gyō henkaku katsuyō, sa-row irregular conjugation).

ka-group

which also has one member, 来る (kuru, "to come"). The Japanese name for this class is カ行変格活用 ka-gyō henkaku katsuyō or simply カ変 ka-hen.

Classical Japanese had two further irregular classes, the na-group, which contained 死ぬ (shinu, "to die") and 往ぬ (inu, "to go", "to die"), the ra-group, which included such verbs as あり ari, the equivalent of modern 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 書く kaku, look in the second row to find its root, kak, then in the hypothetical row to get the ending -e, giving the stem form kake. When there are multiple possibilities, they are listed in the order of increasing rarity.

1. The -a and -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 -o form is used only for the volitional mood and the -a form is used in all other cases; see also the conjugation table below.
2. The unexpected ending is due to the verb's root being tsukaw- but [w] only being pronounced before [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 conjugations for a full list.

1. This is an entirely different verb; する suru has no potential form.
2. These forms change depending on the final syllable of the verb's dictionary form (whether u, ku, gu, su, etc.). For details, see Euphonic changes, below, and the article Japanese verb conjugation.

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

僕は姉に納豆を食べさせられた。

Boku wa ane ni nattō o tabesaserareta.

I was made to eat nattō by my (elder) sister.

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

Japanese has a large variety of related pairs of transitive verbs (that take a direct object) and intransitive verbs (that do not usually take a direct object), such as the transitive hajimeru (始める, someone or something begins an activity), and the intransitive hajimaru (始まる, an activity begins).[14][15]

Note: Some intransitive verbs (usually verbs of motion) take what it looks like a direct object, but it is not.[16] For example, hanareru (離れる, to leave):

私は 東京を 離れる。

Watashi wa Tōkyō o hanareru.

I leave Tokyo.

Main article: Japanese equivalents of adjectives

Semantically speaking, words that denote attributes or properties are primarily distributed between two morphological classes (there are also a few other classes):

• adjectival verbs (conventionally called "i-adjectives") (形容詞 keiyōshi) – these have roots and conjugating stem forms, and are semantically and morphologically similar to stative verbs.
• adjectival nouns (conventionally called "na-adjectives") (形容動詞 keiyōdōshi, lit. "adjectival verb") – these are nouns that combine with the copula.

Unlike adjectives in languages like English, 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 motto 'more' and ichiban 'most'.

Every adjective in Japanese can be used in an attributive position. Nearly every Japanese adjective can be used in a predicative position; this differs from English where there are many common adjectives such as "major", as in "a major question", that cannot be used in the predicate position (that is, *"The question is major" is not grammatical English). There are a few Japanese adjectives that cannot predicate, known as 連体詞 (rentaishi, attributives), which are derived from other word classes; examples include 大きな ōkina "big", 小さな chiisana "small", and おかしな okashina "strange" which are all stylistic na-type variants of normal i-type adjectives.

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

1. The attributive and terminal forms were formerly 安き .ki and 安し .shi, respectively; in modern Japanese these are used productively for stylistic reasons only, although many set phrases such as 名無し nanashi (anonymous) and よし yoshi (sometimes written yosh', general positive interjection) derive from them.
2. The imperative form is extremely rare in modern Japanese, restricted to set patterns like 遅かれ早かれ osokare hayakare 'sooner or later', 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. ii is not treated separately, because all conjugation forms are identical to those of yoi.

1. note that these are just forms of the i-type adjective ない nai
2. 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: 良かろう yokarō 'OK' (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 na-type adjectives, see also the section below on the copula だ da.

The copula da behaves very much like a verb or an adjective in terms of conjugation.

Modern pronunciation is a result of a long history of phonemic drift that can be traced back to written records of the thirteenth century, and possibly earlier. However, it was only in 1946 that the Japanese ministry of education modified existing kana usage to conform to the 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 palatalized morae yu, yo (ゆ、よ) combine with the initial consonant, if present, yielding a palatalized syllable. The most basic example of this is modern kyō (今日、きょう, today), which historically developed as kefu (けふ) → kyō (きょう), via the efu (えふ) → yō (よう) rule.

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

Among Japanese speakers, it is not generally understood that the historical kana spellings were, at one point, reflective of pronunciation. For example, the modern on'yomi reading yō (よう) for leaf (葉, yō) arose from historical efu (えふ). The latter was pronounced something like [ʲepu] by the Japanese at the time it was borrowed (compare Middle Chinese [jiɛp̚]). However, a modern reader of a classical text would still read this as [joː], the modern pronunciation.

Main article: Japanese verb conjugation

As mentioned above, 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 t-sound, i.e., た ta, て te, たり tari, etc.

* denotes impossible/ungrammatical form.

There is one other irregular change: 行く iku (to go), for which there is an exceptional continuative form: 行き iki + て te → 行って itte, 行き iki + た ta → 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 -i + t- conjugations are instead changed to -ut-, as in omōta (思うた) instead of omotta (思った), as perfective of omou (思う, think). In this example, this can combine with the preceding vowel via historical sound changes, as in shimōta (しもうた) (au → ō) instead of standard shimatta (しまった).

The continuative form of proper adjectives, when followed by polite forms such as ござる (御座る, gozaru) be or zonjiru (存じる, know, think), 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 -masu (〜ます) form, as gozaimasu (ございます) and zonjimasu (存じます) (note the irregular conjugation of gozaru, discussed below), and that these verbs are preceded by the continuative form – -ku (〜く) – of adjectives, rather than the terminal form – -i (〜い) – which is used before the more everyday desu (です, be).

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

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

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

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

There are occasional others, such as -aranai → -annai as in wakaranai (分からない, don't understand) → wakannai (分かんない) and tsumaranai (つまらない, boring) → tsumannai (つまんない) – these are considered quite casual and are more common among the younger generation.

Contractions differ by dialect, but behave similarly to the standard ones given above. For example, in Kansai dialect -te shimau (〜てしまう) → -temau (〜てまう).

Adverbs in Japanese are not as tightly integrated into the morphology as in many other languages. Indeed, adverbs are not an independent class of words, but rather a role played by other words. For example, every adjective in the continuative form can be used as an adverb; thus, 弱い yowai 'weak' (adj) → 弱く yowaku 'weakly' (adv). The primary distinguishing characteristic of adverbs is that they cannot occur in a predicate position, just as it is in English. The following classification of adverbs is not intended to be authoritative or exhaustive.

Verbal adverbs

are verbs in the continuative form with the particle ni. E.g. 見る miru 'to see' → 見に mi ni 'for the purpose of seeing', used for instance as: 見に行く mi ni iku, go to see (something).

Adjectival adverbs

are adjectives in the continuative form, as mentioned above. Example: 弱い yowai 'weak' (adj) → 弱く yowaku 'weakly' (adv)

Nominal adverbs

are grammatical nouns that function as adverbs. Example: 一番 ichiban 'most highly'.

Sound symbolism

are words that mimic sounds or concepts. Examples: きらきら kirakira 'sparklingly', ぽっくり pokkuri 'suddenly', するする surusuru 'smoothly (sliding)', etc.

Often, especially for sound symbolism, the particle to "as if" is used. See the article on Japanese sound symbolism.

Examples of conjunctions: そして soshite 'and then', また mata 'and then/again', etc. Although called "conjunctions", these words are, as English translations show, actually a kind of adverb.

Examples of interjections: はい (hai, yes/OK/uh), へえ (hee, wow!), いいえ (iie, no/no way), おい (oi, hey!), etc. This part of speech is not very different from that of English.

Main article: Japanese particles

Particles in Japanese are postpositional, as they immediately follow the modified component. A full listing of particles is beyond the scope of this article, so only a few prominent particles are listed here. Keep in mind that the pronunciation and spelling differ for the particles wa (は), e (へ) and o (を): This article follows the Hepburn-style of romanizing them according to the pronunciation rather than spelling.

The complex distinction between the so-called topic (は wa) and subject (が ga) particles has been the theme of many doctoral dissertations and scholarly disputes. The clause 象は鼻が長い zō-wa hana-ga nagai is well known for appearing to contain two subjects. It does not simply mean "the elephant's nose is long", as that can be translated as 象の鼻は長い zō-no hana-wa nagai. Rather, a more literal translation would be "(speaking of) the elephant, its nose is long", furthermore, as Japanese does not distinguish between singular and plural the way English does, it could also mean "as for elephants, their noses are long".

Two major scholarly surveys of Japanese linguistics in English, (Shibatani 1990) and (Kuno 1973), clarify the distinction. To simplify matters, the referents of wa and ga in this section are called the topic and subject respectively, with the understanding that if either is absent, the grammatical topic and subject may coincide.

As an abstract and rough approximation, the difference between wa and ga is a matter of focus: wa gives focus to the action of the sentence, i.e., to the verb or adjective, whereas ga gives focus to the subject of the action. However, a more useful description must proceed by enumerating uses of these particles.

However, when first being introduced to the topic and subject markers wa and ga most are told that the difference between the two is simpler. The topic marker, wa, is used to declare or to make a statement. The subject marker, ga, is used for new information, or asking for new information.

See Topic marker: Japanese: は.

The use of wa to introduce a new theme of discourse is directly linked to the notion of grammatical theme. Opinions differ on the structure of discourse theme, though it seems fairly uncontroversial to imagine a first-in-first-out hierarchy of themes that is threaded through the discourse. Of course, human limitations restrict the scope and depth of themes, and later themes may cause earlier themes to expire. In these sorts of sentences, the steadfast translation into English uses constructs like "speaking of X" or "on the topic of X", though such translations tend to be bulky as they fail to use the thematic mechanisms of English. For lack of a comprehensive strategy, many teachers of Japanese emphasize the "speaking of X" pattern without sufficient warning.

ジョンは学生です。

JON wa gakusei desu

(On the topic of) John, (he) is a student.

A common linguistic joke shows the insufficiency of rote translation with the sentence 僕はウナギだ boku wa unagi da, which per the pattern would translate as "I am an eel." (or "(As of) me is eel"). Yet, in a restaurant this sentence can reasonably be used to say "My order is eel" (or "I would like to order an eel"), with no intended humour. This is because the sentence should be literally read, "As for me, it is an eel," with "it" referring to the speaker's order. The topic of the sentence is clearly not its subject.

Related to the role of wa in introducing themes is its use in contrasting the current topic and its aspects from other possible topics and their aspects. The suggestive pattern is "X, but..." or "as for X, ...".

雨は降っていますが...

ame wa futte imasu ga...

The rain is falling, but...

Because of its contrastive nature, the topic cannot be undefined.

*誰かは本を読んでいる。

*dareka wa hon o yonde iru

*Someone is reading the book.

In this use, ga is required.

In practice, the distinction between thematic and contrastive wa is not that useful. Suffice it to say that there can be at most one thematic wa in a sentence, and it has to be the first wa if one exists, and the remaining was are contrastive. For completeness, the following sentence (due to Kuno) illustrates the difference.

僕が知っている人は誰も来なかった。

boku ga shitte iru hito wa daremo konakatta

(1) Of all the people I know, none came.

(2) (People came but), there weren't any of the people I know.

The first interpretation is the thematic wa, treating "the people I know" (boku ga shitte iru hito) as the theme of the predicate "none came" (dare mo konakatta). That is, if I know A, B, ..., Z, then none of the people who came were A, B, ..., Z. The second interpretation is the contrastive wa. If the likely attendees were A, B, ..., Z, and of them I know P, Q and R, then the sentence says that P, Q and R did not come. The sentence says nothing about A', B', ..., Z', all of whom I know, but none of whom were likely to come. (In practice the first interpretation is the likely one.)

Unlike wa, the subject particle ga nominates its referent as the sole satisfier of the predicate. This distinction is famously illustrated by the following pair of sentences.

ジョンさんは学生です。

Jon-san wa gakusei desu

John is a student. (There may be other students among the people we're talking about.)

(このグループの中で)ジョンが学生です。

(Kono gurūpu no naka de) Jon ga gakusei desu

(Of all the people we are talking about) it is John who is the student.

It may be useful to think of the distinction in terms of the question each statement could answer, e.g.:

ジョンさんの仕事は何ですか。

Jon-san no shigoto wa nan desu ka

What is John's occupation?

for the first statement, versus

どちらの方が学生ですか。

Dochira no kata ga gakusei desu ka

Which one (of them) is the student?

for the second.

Similarly, in a restaurant, if the waitress asks who has ordered the eels, the customer who ordered it can say

僕がウナギだ。

Boku ga unagi da

The eels are for me (not these other people).

For certain verbs, typically ga instead of o is used to mark what would be the direct object in English:

ジョンさんはフランス語が出来る。

Jon-san wa furansu-go ga dekiru

John knows French.

These notions that would be thought of as actions, or "verbs" in English, e.g. 出来る (to be able to), ほしい (is/are desirable), 好きだ (is/are liked), 嫌いだ (is/are disliked), etc., are in fact simply adjectives and intransitive verbs whose subject is what would be a direct object in the English translation. The equivalent of the English subject is instead the topic in Japanese and thus marked by wa, reflecting the topic-prominent nature of Japanese grammar.

The direct object of transitive verbs is indicated by the object particle を o.

ジョンさんは青いセーターを着ている。

Jon-san wa aoi sētā o kite iru

John is wearing a blue sweater.

This particle can also mean "through" or "along" or "out of" when used with motion verbs.

メアリが細い道を歩いていた。

MEARI ga hosoi michi o aruite ita

Mary was walking along a narrow road.

国境の長いトンネルを抜けると雪国であった。

kokkyō no nagai TONNERU o nukeru to yukiguni de atta

The train came out of the long tunnel into the snow country.

The general instrumental particle is で de, which can be translated as "using" or "by":

肉はナイフで切ること。

niku wa NAIFU de kiru koto

Meat must be cut with a knife.

電車で行きましょう。

densha de ikimashō

Let's go by train.

This particle also has other uses: "at" (temporary location):

町角で先生に会った。

machikado de sensei ni atta

(I) met my teacher at the street corner.

"In":

海で泳ぐのは難しい。

umi de oyogu no wa muzukashii

Swimming in the sea is hard.

"With" or "in (the span of)":

劇は主人公の死で終る。

geki wa shujinkō no shi de owaru

The play ends with the protagonist's death.

俺は二秒で勝つ。

ore wa nibyō de katsu

I'll win in two seconds.

The general locative particle is に ni.

東京に行きましょう。

Tōkyō ni ikimashō

Let's go to Tokyo

In this function it is interchangeable with へ e. However, ni has additional uses: "at (prolonged)":

私は大手町一丁目99番地に住んでいます。

watashi wa Ōtemachi itchōme 99 banchi ni sunde imasu

I live at Ōtemachi ichōme 99 banchi.

"On":

氷は水に浮く。

kōri wa mizu ni uku

Ice floats on water.

"In (some year)", "at (some point in time)":

春の夕暮れに......

haru no yūgure ni...

On a spring eve...

To conjoin nouns, と to is used.

かばんには、教科書三冊と漫画本五冊を入れています。

Kaban ni wa kyōkasho san-satsu to manga-bon go-satsu o irete imasu

I have three textbooks and five comic books in the bag.

The additive particle も mo can be used to conjoin larger nominals and clauses.

ヨハンはドイツ人だ。ブリゲッタもドイツ人だ。

YOHAN wa DOITSU-jin da. BURIGETTA mo DOITSU-jin da

Johann is a German. Brigitte is a German too.

彼は映画スターであり、政治家でもある。

kare wa eiga SUTĀ de ari, seijika de mo aru

He is a movie star and also a politician.

For an incomplete list of conjuncts, や ya is used.

ボリスやイバンを呼べ。

BORISU ya IBAN o yobe

Call Boris, Ivan, etc.

When only one of the conjuncts is necessary, the disjunctive particle か ka is used.

寿司か刺身か、何か注文してね。

sushi ka sashimi ka, nanika chūmon shite ne

Please order sushi or sashimi or something.

Quantities are listed between から kara 'from' and まで made 'to'.

華氏92度から96度までの熱は心配するものではない。

Kashi 92 do kara 96 do made no netsu wa shinpai suru mono de wa nai

A temperature between 92 Fahrenheit and 96 is not worrisome.

This pair can also be used to indicate time or space.

朝9時(午前9時)から11時まで授業があるんだ。

asa ku-ji kara jūichi-ji made jugyō ga aru n da

You see, I have classes between 9 a.m. and 11 a.m.

Because kara indicates starting point or origin, it has a related use as "because", analogously to English "since" (in the sense of both "from" and "because"):

スミスさんはとても積極的な人ですから、いつも全部頼まれているのかもしれません。

SUMISU-san wa totemo sekkyokuteki na hito desu kara, itsumo zenbu tanomarete iru no kamoshiremasen

Mr. Smith, because you're so assertive, you may always be asked to do everything.

The particle kara and a related particle yori are used to indicate lowest extents: prices, business hours, etc.

私たちの店は7時より営業しております。

Watashitachi no mise wa shichi-ji yori eigyō shite orimasu

Our shop is open for business from 7 onwards.

Yori is also used in the sense of "than".

お前は姉ちゃんよりうるさいんだ!

omae wa nē-chan yori urusai n da

You are louder/more talkative than my elder sister!

The particle と to is used to set off quotations.

「殺して... 殺して」とあの子は言っていた。

"koroshite... koroshite" to ano ko wa itteita

The girl was saying, "Kill me... kill me."

猫がニャーニャーと鳴く。

neko ga NYĀ NYĀ to naku

The cat says meow, meow.

It is also used to indicate a manner of similarity, "as if", "like" or "the way".

彼は「愛してるよ」と言って、ぽっくりと死んだ。

kare wa "aishiteru yo" to itte, pokkuri to shinda

He said "I love you," and dropped dead.

In a related conditional use, it functions like "after/when", or "upon".

雨が上がると、子ども達は授業を忘れて、日の当たっている水たまりの誘惑に夢中になる。

ame ga agaru to, kodomo-tachi wa jugyō o wasurete, hi no atatteiru mizutamari no yūwaku ni muchū ni naru

Rain stops and then: children, forgetting their lessons, give in to the temptation of sun-faced puddles.

国境の長いトンネルを抜けると雪国であった。

kokkyō no nagai TONNERU o nukeru to, yukiguni de atta

The train came out of the long tunnel (and then) into the snow country.

Finally it is used with verbs like to meet (with) (会う au) or to speak (with) (話す hanasu).

ジョンがメアリーと初めて会ったのは、1942年の春の夕暮れ時のことだった。

JON ga MEARI to hajimete atta no wa, 1942 nen no haru no yūguredoki no koto datta

John met Mary for the first time on a dusky afternoon of spring in 1942.

This last use is also a function of the particle に ni, but to indicates reciprocation which ni does not.

ジョンはメアリーと恋愛している。(usually say ジョンはメアリーと付き合っている。)

JON wa MEARI[Ī] to ren'ai shite iru (JON wa MEARI[Ī] to tsukiatte iru)

John and Mary are in love.

ジョンはメアリーに恋愛している。(usually say ジョンはメアリーに恋している。)

JON wa MEARI[Ī] ni ren'ai shite iru (JON wa MEARI[Ī] ni koi shite iru)

John loves Mary (but Mary might not love John back).

Finally, the particle よ yo is used in a hortative or vocative sense.

可愛い娘よ、私に顔をしかめるな。

kawaii musume yo, watashi ni kao o shikameruna

Oh my beloved daughter, don't frown at me so!

The sentence-final particle か ka turns a declarative sentence into a question.

そちらはアメリカ人でしょうか?

sochira wa amerika-jin deshō ka?

Are you perchance an American?

Other sentence-final particles add emotional or emphatic impact to the sentence. The particle ね ne softens a declarative sentence, similar to English "you know?", "eh?", "I tell you!", "isn't it?", "aren't you?", etc.

彼に電話しなかったのね。

kare ni denwa shinakatta no ne

You didn't call him up, did you?

近々ロンドンに引っ越されるそうですね。

chikajika rondon ni hikkosareru sō desu ne.

I hear you're moving to London soon. Is that true?

A final よ yo is used in order to soften insistence, warning or command, which would sound very strong without any final particles.

嘘なんかついてないよ！

uso nanka tsuite nai yo!

I'm not lying!

There are many such emphatic particles; some examples: ぜ ze and ぞ zo usually used by males; な na a less formal form of ne; わ wa used by females (and males in the Kansai region) like yo, etc. They are essentially limited to speech or transcribed dialogue.

Compound particles are formed with at least one particle together with other words, including other particles. The commonly seen forms are:

• particle + verb (term. or cont. or -te form)
• particle + noun + particle
• noun + particle

Other structures are rarer, though possible. A few examples:

その件に関して知っている限りのことを教えてもらいたい。

sono ken ni kan-shite shitte-iru kagiri no koto o oshiete moraitai

Kindly tell me everything you know concerning that case. (particle + verb in cont.)

外国語を学習する上で大切なことは毎日の努力がものを言うということである。

gaikokugo o gakushū suru ue de taisetsu na koto wa mainichi no doryoku ga mono o iu to iu koto de aru

In studying a foreign language, daily effort gives the most rewards. (noun + particle)

兄は両親の心配をよそに、大学をやめてしまった。

ani wa ryōshin no shinpai o yoso ni, daigaku o yamete shimatta

Ignoring my parents' worries, my brother dropped out of college. (particle + noun + particle)

All auxiliary verbs attach to a verbal or adjectival stem form and conjugate as verbs. In modern Japanese there are two distinct classes of auxiliary verbs:

Pure auxiliaries (助動詞 jodōshi)

are usually just called verb endings or conjugated forms. These auxiliaries do not function as independent verbs.

Helper auxiliaries (補助動詞 hojodōshi)

are normal verbs that lose their independent meaning when used as auxiliaries.

In classical Japanese, which was more heavily agglutinating than modern Japanese, the category of auxiliary verb included every verbal ending after the stem form, and most of these endings were themselves inflected. In modern Japanese, however, some of them have stopped being productive. The prime example is the classical auxiliary たり -tari, whose modern forms た -ta and て -te are no longer viewed as inflections of the same suffix, and can take no further affixes.

¹ ます masu has stem forms: irrealis ませ and ましょ, continuative まし, terminal ます, attributive ます, hypothetical ますれ, imperative ませ.

² られる rareru in potential usage is sometimes shortened to れる reru (grp. 2); thus 食べれる tabereru 'to be able to eat' instead of 食べられる taberareru. But it is considered non-standard.

³ Technically, such an auxiliary verb る, ru, denoting the potential form, does not exist, as for example 飲める nomeru is thought to actually come from the contraction of 飲み得る, nomieru (see below). However, textbooks tend to teach it this way. (飲める in old texts would have been the attributive past tense form of 飲む instead of the potential meaning.)

⁴ させる saseru is sometimes shortened to さす sasu (grp. 1), but this usage is somewhat literary.

Much of the agglutinative flavour of Japanese stems from helper auxiliaries, however. The following table contains a small selection of many such auxiliary verbs.

• Note: 得る eru/uru is the only modern verb of shimo nidan type (and it is different from the shimo nidan type of classical Japanese), with conjugations: irrealis え, continuative え, terminal える or うる, attributive うる, hypothetical うれ, imperative えろ or えよ.