Old Japanese nominals tend to have simple morphology and little fusion, in contrast to the complex inflectional morphology of verbs. Japanese at all stages has used prefixes with both nouns and verbs, but Old Japanese also used prefixes for grammatical functions later expressed using suffixes. This is atypical of SOV languages, and may suggest that the language was in the final stage of a transition from a SVO typology.
Nominals Pronouns Old Japanese include
personal pronouns,
demonstratives and an isolated
interrogative pronoun 'what'. Many pronouns have both a short form and a longer form with attached of uncertain etymology. If the pronoun occurs in isolation, the longer form is used. The short form is used with genitive particles or in nominal compounds, but in other situations either form is possible. Personal pronouns are distinguished by taking the
genitive marker , in contrast to the marker used with demonstratives and nouns. • The first-
person pronouns, and , are used for the singular and plural respectively, though with some overlap. The forms are also used
reflexively, which suggests that was originally an
indefinite pronoun and gradually replaced . • The second-person pronoun is . • The third-person pronoun is much less commonly used than the non-proximal demonstrative from which it was derived. • There is also an interrogative pronoun and a reflexive pronoun . Demonstratives often distinguish proximal (to the speaker) and non-proximal forms marked with and respectively. Many forms have corresponding interrogative forms . In Early Middle Japanese, the non-proximal forms were reinterpreted as hearer-based (medial), and the speaker-based forms were divided into proximal forms and distal / forms, yielding the three-way distinction that is still found in Modern Japanese.
Numerals In later texts, such as the ''Man'yōshū'', numerals are sometimes written using Chinese logographs, which give no indication of pronunciation. The following numerals are attested phonographically: The forms for 50 and 70 are known only from Heian texts. There is a single example of a phonographically recorded compound number, in
Bussokuseki 2: {{interlinear|lang=ojp|indent=3 This example uses the
classifiers (used with tens and hundreds) and (used with digits and hundreds). The only attested ordinal numeral is 'first'. In
Classical Japanese, the other ordinal numerals have the same form as cardinals. This may also have been the case for Old Japanese, but there are no textual occurrences to settle the question.
Classifiers The
classifier system of Old Japanese is much less developed than at later stages of the language, and classifiers are not obligatory between numerals and nouns. A few bound forms are attested phonographically: (used with digits and hundreds), (used with tens and hundreds), (for people), , (for grassy plants) and (for days). Many ordinary nouns can also be used either freely or as classifiers.
Prefixes Old Japanese nominal prefixes include honorific , intensive from 'truth', diminutive or affectionate and a prefix of uncertain function.
Suffixes Old Japanese nominals have suffixes or particles to mark diminutives, plural number and case. When multiple suffixes occur, case markers come last. Unmarked nouns (but not pronouns) are neutral as to number. The main plural markers are the general-purpose and two markers restricted to animate nouns, (limited to five words) and . The main case particles are •
accusative marks objects (as in later Japanese) but also adverbials of duration. •
genitive (unrestricted) and (restricted to people). In
Late Middle Japanese, shifted to a
nominative case marker. •
dative or
locative •
ablative ~ ~ ~ from 'after(wards)'. Only the form survived in Early Middle Japanese. •
comitative The subject of a sentence is usually not marked. There are a few cases in the
Senmyō of subjects of active verbs marked with a suffix , which is thought to be an archaism that was obsolete in the Old Japanese period.
Verbs Old Japanese has a richer system of verbal suffixes than later forms of Japanese. Old Japanese verbs use
inflection for
modal and
conjunctional purposes. Other categories, such as
voice,
tense,
aspect and
mood, are expressed by using optional suffixed
auxiliaries, which are also inflected:
Inflected forms As in later forms of Japanese, Old Japanese verbs have a large number of inflected forms. In traditional Japanese grammar, they are represented by six forms (, ) from which all the others may be derived in a similar fashion to the
principal parts used for
Latin and other languages: ; (irrealis) :This form never occurs in isolation but only as a stem to which several particles and auxiliaries are attached. This stem originated from resegmentation of an initial of several suffixes (auxiliary verbs) as part of the stem. ; (adverbial, infinitive) :This form is used to mark a predicate as coordinate with a following predicate. It also serves as a stem for auxiliaries expressing tense and aspect, as well as suffixes and of adverbial subordinate forms. ; (conclusive, predicative) :This form is used as the main verb concluding a declarative sentence. It is also used as a stem to which modal extensions, final particles, and some conjunctional particles are attached. The conclusive form merged with the attributive form by about 1600, but the distinction is preserved in the Ryukyuan languages and Hachijō. ; (attributive, adnominal) :This form is used as the verb in a nominalized clause or a clause modifying a noun. It also serves as a stem for the nominalizing suffix and most conjunctional particles. ; (realis, exclamatory, subjunctive) :This form is used as the main verb in an exclamatory sentence or as the verb in an adverbial clause. It also serves as a stem for the particles (provisional) and (concessive). ; (imperative) :This form expresses the
imperative mood. This system has been criticized because the six forms are not equivalent, with one being solely a combinatory stem, three solely word forms, and two being both. It also fails to capture some inflected forms. However, five of the forms are basic inflected verb forms, and the system also describes almost all extended forms consistently.
Conjugation classes Old Japanese verbs are classified into eight conjugation classes that were originally defined for the classical Japanese of the late Heian period. In each class, the inflected forms showed a different pattern of rows of a kana table. These rows correspond to the five vowels of later Japanese, but the discovery of the A/B distinction in Old Japanese showed a more refined picture. Three of the classes are grouped as consonant bases: ; (quadrigrade) :This class of regular consonant-base verbs includes approximately 75% of verbs. The class is so named because the inflections in later forms of Japanese span four rows of a table, corresponding to four vowels. However, the discovery of the A/B distinction revealed that this class actually involved five different vowels in Old Japanese, with distinct vowels
e1 and
e2 in the exclamatory and imperative forms respectively. The bases are almost all of the form (C)VC-, with the final consonant being
p,
t,
k,
b,
g,
m,
s or
r. ; (
n-irregular) :The three
n-base verbs form a class of their own: 'die', 'depart' and the perfective auxiliary . They are often described as a "hybrid" conjugation because the adnominal and exclamatory forms follow a similar pattern to vowel-base verbs. ; (
r-irregular) :The irregular
r-base verbs are 'be, exist' and other verbs that incorporate it, as well as 'be sitting', which became the existential verb in later forms of Japanese. The distinctions between
i1 and
i2 and between
e1 and
e2 are eliminated after
s,
z,
t,
d,
n,
y,
r and
w. There are five vowel-base conjugation classes: ; (lower bigrade or
e-bigrade) :The largest regular vowel-base class ends in
e2 and includes approximately 20% of verbs. ; (upper bigrade or
i-bigrade) :This class includes about 30 verbs whose bases end in
i2. ; (upper monograde or
i-monograde) :This class contains about 10 verbs of the form (C)
i1-. Some monosyllabic
i-bigrade verbs had already shifted to this class by Old Japanese, and the rest followed in Early Middle Japanese. ; (
k-irregular) :This class consists of the single verb 'come'. ; (
s-irregular) :This class consists of the single verb 'do'. Early Middle Japanese also has a (lower monograde or
e-monograde) category, consisting of a single verb 'kick', which reflects the Old Japanese lower bigrade verb . The bigrade verbs seem to belong to a later layer than other verbs. Many
e-bigrade verbs are
transitive or
intransitive counterparts of consonant-base verbs. In contrast,
i-bigrade verbs tend to be intransitive. Some bigrade bases also appear to reflect pre-Old-Japanese adjectives with vowel stems combined with an
inchoative *-i suffix: • *-a-i >
-e2, e.g. 'redden, lighten' vs 'red'. • *-u-i >
-i2, e.g. 'get desolate, fade' vs 'lonely'. • *-ə-i >
-i2, e.g. 'get big, grow' vs 'big'.
Copulas Old Japanese has two copulas with limited and irregular conjugations: The form had a limited distribution in Old Japanese, and disappeared in Early Middle Japanese. In later Japanese, the form became , but these forms have otherwise endured to modern Japanese.
Verbal prefixes Japanese has used verbal prefixes conveying emphasis at all stages, but Old Japanese also has prefixes expressing grammatical functions, such as reciprocal or cooperative (from 'meet, join'), stative (from 'exist'), potential (from 'get') and prohibitive , which is often combined with a suffix .
Verbal auxiliaries Old Japanese has a rich system of auxiliary elements that can be suffixed to verb stems and are themselves inflected, usually following the regular consonant-stem or vowel-stem paradigms, but never including the full range of forms found with full verbs. Many of these disappeared in later stages of the language. Tense and aspect are indicated by suffixes attached to the infinitive. The tense suffixes are: • the simple past (conclusive), (adnominal), (exclamatory). The variation may indicate an origin in multiple forms. Indeed counterparts of are absent from Ryukyuan and weakly attested in Eastern Old Japanese. • the modal past or retrospective , a fusion of the simple past with 'exist'. • the past conjectural , a fusion of the simple past with the conjectural suffix . The perfective suffixes are and . During the
Late Middle Japanese period, the tense and aspect suffixes were replaced with a single past-tense suffix , derived from + 'exist' > . However, the Hachijō language retains some of the early tense and aspect system, in particular reflexes of the old past suffix and the distinction between and forms. Other auxiliaries are attached to the irrealis stem: • the negative and < * • the passive and • the causative • the honorific • the iterative or • the conjectural or tentative • the subjunctive The honorific and iterative ceased to be productive in Middle Japanese. During the Early Middle Japanese period, the causative was replaced by .
Adjectives Old Japanese adjectives were originally nominals and, unlike in later periods, can be used uninflected to modify following nouns. They can also take a suffix (an adjectival copula), forming
stative verbs conjugated in two classes: The second class, with stems ending in , differs only in the conclusive form, whose suffix was dropped by
haplology. Adjectives of this class tend to express more subjective qualities. Many of them were formed from a verbal stem by the addition of a suffix of uncertain origin. Towards the end of the Old Japanese period, a more expressive conjugation was formed by adding the verb 'be' to the infinitive, with the sequence reducing to : Many
adjectival nouns of Early Middle Japanese were based on Old Japanese adjectives that were formed with suffixes , or . == Syntax ==