The imperfect(ive), present or non‑past form is broadly equivalent to the present and future tenses of English. In Japanese, the imperfective form is used as the headword or lemma, hence the name dictionary form. The terms conclusive, concluding, final, predicative, etc. are used for any form that occurs at the end of a sentence, whether imperfect or perfect; and attributive, adnominal, adjectival, substantival, etc. for any form that occurs before a noun. However, in modern Japanese, only the imperfect makes this distinction between "conclusive" and "attributive" in certain cases, particularly in adjectives (more in the subsection below) and copulae; conclusives and attributives are more distinct in classical Japanese.
The imperfect, when used as a predicate (the "conclusive"), generally conveys a present time, an existent habit, a future time and the historical present, which coincides with the simple present and various ways to express the future ("will do," "be going to do," "be doing") in English. However, for certain verbs, the simple imperfect does not suffice to express the same idea as the English "simple present," and the gerundive ‑te iru is required, thus , not *. Before a noun (the "attributive"), it may be the perfect ‑ta that expresses the "simple present," as in . In yet more complex sentence, the simple imperfect is expected, such as . Polysemous verbs may or may not require the gerund depending on the various senses that they possess.
Imperfective form example sentences English Japanese Function Everybody dies. eternal fact a person who loves nature I would sacrifice my life without hesitation for someone I loved. All the trains bound for Tokyo are terribly overcrowded. Our cat's tail is black at the tip. Before my eyes a black cat dashed across my path. I have bitter memories of that summer. present state This can be illustrated from my own personal experience. I'm so annoyed that I feel like crying. I saw a red light ahead. It's that time of year when saury is at its tastiest. I go abroad at my own expense. existent habit I usually go swimming in the ocean every summer. I'll go to Osaka on the first flight tomorrow morning. future action Hi there, where are you going? They will liquidate the company by the end of next February.
Conjugation table Historically, the vowel u systemically fused with its preceding vowel into one long vowel, which yielded such pronunciation as . These fusions are complete in some western dialects, but others still make exceptions for verbs ending in u. Compare the following, whereby the unfused forms are listed first: , , , . In classical Japanese, the fused forms are traditionally used, regardless of the kana spelling, which is the case for not only the said example godan verbs, but also nidan verbs such as , although modern Tokyo speakers may rather use the spelling pronunciation kangau. Some highly elevated verbs such as and accept the fused forms as standard rather than dialectal alternatives. Fusions occur more extensively for the gerund and perfective.
Among verbs ending in the vowel u, the verb exceptionally only takes the fused form yū, never the unfused *iu, not even in careful speech. Despite the pronunciation, its standard kana spelling is still , not , (although the latter is still listed in dictionaries, and can be used, apart from or just , as a nonstandard alternative to reflect the actual pronunciation). This convention, along with the particles , and , is retained from historical kana orthography for practical purposes. For , the kana spelling is in keeping with other conjugational forms such as and . is possibly homophonous with , except that the latter can be unaccented or accented, while the former is only unaccented. In this article, the more phonetically accurate spelling is used in the conjugation tables below not to obscure phonetic changes between verb forms. The yu‑ resulting from the fusion in yū has begun to spread to other forms, such as yuwa‑, yutte and yutta, whose statuses are certain, although the statuses of yui, yue and especially yuō are dubious. It has been claimed that there are dialects where yui nagara, yueba and yue have occurred.
Aru is now a full-fledged godan verb, but it used to belong to an irregular class called in classical Japanese. Although having been long displaced by its attributive aru, its distinct conclusive ari lingers on in some proverbial cliches, such as , , etc., or the pseudoclassical baseball cliche .
Certain ‑suru or ‑zuru verbs and their godan and ichidan equivalents are interchangeable (or at least sensitive to specifically what follows them) and even used in the same text, although it has been claimed that, at least for the conclusive/attributive form, the more classical//western ‑zuru variants are more "formal" and "basically a written form", compared to the more modern//eastern ‑jiru variants. The ‑su variants are highly inconsistent across verbs, and even for highly "godan‑ized" verbs like , whose other forms are predominantly godan, the conclusive/attributive aisuru and conditional aisureba in particular are still preferred to the fully godan variants aisu and aiseba. In some cases it is not clear whether aisu is godan or actually pseudo-classical, for example in where all ‑suru verbs can optionally lose the ru. In classical or pseudo-classical literature, aisu is more likely to be conclusive and aisuru is more likely to be attributive or nominalized.
The extenders beshi, beki, beku, mai, maji, majiki, majiku, etc., can stylistically take classical conclusives before them, including the irregular and , and the nidan , , , , etc. These can be substituted with the modern irregular and , and the ichidan , , , , etc. Some governmental institutions have shifted away from the nidan style () in favor of the ichidan style (). With the classical irregular conclusive and its derivatives, however, the attributive is used instead, as in , , etc. rather than *ari beki, *yokari beki, etc., and such exceptions coincide with the modern godan conclusives ending in aru of the same verbs and adjectives.
The irregular and nidan verbs all have attributives distinct from conclusives, which have been employed in writing for literary flair. However, the current convention is to steer away from these elevated archaisms, which means that instead of a classical nidan conclusive like the passive and a nidan attributive like , a modern ichidan conclusive/attributive like is recommended.
When used in modern Japanese, nidan verbs are only formally distinct from their ichidan counterparts in their conclusives, attributives and provisionals, which all contain the vowel u instead of i or e. Certain nidan verbs, such as and , may have two ichidan counterparts for each, one being kamiichidan ("upper unigrade") with the vowel i, and the other being shimoichidan ("lower unigrade") with the vowel e, and they may differ in transitivity, which is made morphologically obvious in the ichidan conclusives, attributives and provisionals compared to their nidan ancestors.
The attributive expression derives from the attributive of , which in turn is an archaic e-stemmed nidan passive, equivalent to the archaic/elevated nidan iwaru(ru) and the modern ichidan iwareru, of .
Since nidan verbs can be used before extenders, so-called "yodan verbs" presumably can as well, but as their conclusives/attributives are indistinguishable from so-called "godan verbs," it is rather a matter of classical fused pronunciation versus modern unfused pronunciation than truly distinct verb forms.
The classical forms of the now ichidan verb are deku and , which belong to the same irregular class as ku and . While deku can be used before beki, etc as in deku beki, etc, it is also possible to use the infinitive deki instead as in deki beki, etc.
The verb is now a full-fledged godan verb in mainstream Japanese, but it used to belong to its own irregular class () with the now obsolete . It had a distinct attributive and provisional which have been used elevatedly.
The classical attributives of ‑ta/‑da are ‑taru/‑daru, which have been used elevatedly just like nidan attributives (compare the copular attributive na(ru)). The classical ‑tari/‑dari are not really used conclusively as true conclusives, where the modern ‑ta/‑da are still preferred; the formally identical infinitives ‑tari/‑dari evolved into modern representatives.
The politeness auxiliary ‑masuru is characterized as "pseudo-literary" or faux archaic. It was used in parliamentary speech during the 20th century, but usage drastically declined into the 21st century. Some examples include , , . The conjugational similarity between ‑masu and suru suggests an etymological link.
The sound sequence , with /V/ being a vowel, is often colloquially and masculinely fused into a long vowel. Since all adjectival conclusive/attributive forms have this sound sequence, they are liable to such fusion. Most adjectives of this kind remain distinctly masculine, and their phonetic spellings are found in written dialog for masculine characters in fiction, such as , , , , , , , , , , etc. Non-masculine examples include , and . See for further citations.
The classical conclusives nashi and yoshi in particular are now more of cliches rather than catch-all representatives of adjectives in general. Nashi is often used as a nominal suffix meaning "without", "‑less" or "‑free", as in . Yoshi is often used as an interjection meaning "Good!" or "Alright!". The classical onaji has evolved into an adjectival noun (onaji da/de aru/desu, onaji (na), etc.), and despite being originally conclusive, it is now prevalently attributive. Other examples of classical conclusives for cliched, proverbial and elevated uses include , , , , etc.
The classical attributive ending ‑ki, the ancestor of the modern attributive/conclusive ending ‑i, is still used in elevated cliches and titles for books and fictional characters, such as , , , , , , , , , etc.
The attributive ending ‑karu, a fusion of the infinitive ending ‑ku and the verb aru, is uncommon in modern Tokyo Japanese. It has been found in such constructions with ‑beki as . In Kyushu, ‑karu was reduced further to ‑ka, and yoka is used instead of either yoi or yoshi.
Note that not all adjectives have classical counterparts. For example, is a modern adjective with no classical counterpart to speak of, which means such forms as ōkiki and ōkikaru are merely pseudo-classical.
The classical adjectival extenders beshi, gotoshi and maji are still used in elevated language. Their attributives retain the ‑ki ending as in beki, gotoki, majiki, although the ‑i ending as in bei, majii has historically and dialectally occurred. For beshi in particular, its attributive beki can be used conclusively in the phrase beki da/de aru/desu. For more examples, see #Imperfective: Grammatical compatibility below.
Conclusive form Attributive form Interchangeable counterpart Godan and pseudo-yodan verbs Ichidan verbs Pseudo-nidan verbs Irregular verbs Verbal auxiliaries Adjectives and adjectival auxiliaries Special auxiliaries
Grammatical compatibility The imperfective conclusive/attributive form can be followed by various extenders.