Chapter 70Person–Number Interactions and Plural Agreement

70.1 Two layers of number

Person and number meet in Hokkaido Ainu at two formally distinct layers. Within the personal-affix paradigm, number is built into specific person rows: the first plural exclusive series (ci=/=as/un=), second plural eci=, and the fourth-person series, whose number behavior is reference-dependent rather than form-fixed. Verbal number forms a second layer, realized through suppletive singular/plural stem alternations and through two homophonous formatives: a root-attaching plural suffix -pa and an outer plural auxiliary or element pa that follows the person-inflected verb Nakagawa (2024: 140–162); Bugaeva (2012: 471); Nakagawa (2022). The person inventory is set out in Chapter 62 (Architecture of the Personal-Affix System: The Four Persons and the S/A/O Paradigms); the stem alternations in Chapter 58 (Verbal Number: Suppletive Stems and the Pluractional -pa); the exclusive row and clusivity in Chapter 64 (First-Person Plural and the Clusivity Question (ci=/=as, un=)); and the full range of fourth-person functions in Chapter 67 (The Indefinite/Fourth Person: Forms, Reference, and Agent-Defocusing).

Corbett's distinction between the indexing of participant number and the marking of event or action number (Corbett 2000) maps onto these two layers. Intransitive plural marking in Hokkaido is agreement-like: the number of S determines both the stem choice and the S-affix form. Transitive plural marking is oriented primarily to the object or to the action, bringing it closer to event-number marking in Corbett's terms Nakagawa (2024: 142–145).

70.2 What controls the plural verb

With intransitive verbs the plural stem — whether suppletive (ek/arki 'come', arpa/paye 'go', an/oka(y) 'exist') or suffixal (V/-pa pairs such as rewe/rew-pa) — agrees with S. The 1PL.EXCL suffix =as and a plural fourth-person suffix =an both obligatorily co-occur with a plural intransitive stem; a singular S affix selects the singular stem Nakagawa (2024: 142–146); Bugaeva (2012: 471).

With transitive verbs the picture diverges. Plural marking is tied primarily to the plurality of O or of the action; a first- or fourth-person plural A prefix (ci=, a=) does not by itself reliably trigger the plural stem or outer pa. Nakagawa characterises intransitive plural as agreement-like and transitive plural as action- or object-oriented and often optional Nakagawa (2024: 142–146); Bugaeva (2012: 471). Ijäs's learner grammar states the same split: intransitive plural follows S, transitive plural ordinarily follows O or the action Ijäs (2023). The corpus shows verb-specific and dialect-variable departures from any simple threshold, and Nakagawa's discussion of numerals and quantifiers treats the co-occurrence with plural morphology as complex and speaker-variable Nakagawa (2024: 160–162).

70.3 Stem-forming -pa and outer pa

Nakagawa distinguishes the two pa elements by their position relative to the person-inflected form. Stem-forming -pa builds the plural member of a V/-pa pair and attaches to the root, inside any person marker or causative suffix. Outer pa follows the fully person-inflected verb, outside any person affix, and marks participant or event plurality Nakagawa (2024: 151–159). Sakaguchi applies a formal positional criterion — a clitic (接語) attaches to the person-inflected form rather than to the root — and concludes that the Saru, Chitose, and Ishikari outer element is a clitic, distinct from the root-attaching suffix Sakaguchi (2024: 12, 77–83). The hypothesis that outer pa is a later western Hokkaido development that displaced an earlier pan-Ainu outer (h)ci is argued in Nakagawa (2022) ‹contested›.

The minimal pair demonstrating the position contrast uses the fourth-person intransitive suffix =an. When outer pa is used, it follows =an; when stem-forming -pa is used, it precedes =an.

Outer pa can repeat across conjoined predicates in a clause chain because its scope is over the person-inflected predicate, not over the root. The inner suffix -pa belongs to the stem and contributes its number reading at the lexical level. The two may co-occur on the same verb — a V/-pa stem combined with outer pa — and both combine with causative suffixes while maintaining their respective attachment sites Nakagawa (2024: 156–159).

70.4 Fourth-person plurals and number mismatches

The fourth-person series triggers plural verbal morphology in four of its five uses, regardless of the actual referent count. Nakagawa enumerates five functions at 2024: 174–179; the number behavior follows from the function Nakagawa (2024: 160–161, 174–179); Tamura (1972: 28, 34); Bugaeva (2012: 475–476).

Inclusive first plural (use ①, 'you and I') always takes the plural verb stem, since the referent is inherently multiple Nakagawa (2024: 174); Takahashi (2015: 209). In Tokachi, the inclusive series consistently co-occurs with plural verb forms even when referring to a pair, and this co-selection is obligatory Takahashi (2015: 209).

Honorific second-person address (use ②) requires the plural verb stem for a single addressee, as a form of social amplification Nakagawa (2024: 175–176); Tamura (1972: 28). The mismatch between grammatically plural morphology and a singular referent is systematic and socially conditioned.

Indefinite/impersonal use (use ③) — the equivalent of French on or German man — also takes the plural verb stem, with an unspecified agent defocused from the event Nakagawa (2024: 176–177); Tamura (1972: 34); Satō (2008: 203–205).

Narrative first-person use (use ④) is where dialectal variation is sharpest. In Saru and Chitose, a single protagonist may appear with the singular verb stem. Horobetsu also permits singular stems for a singular narrator, though the only available free pronoun is the formally plural aokay. Shizunai shows the opposite configuration: the verb is consistently plural regardless of narrator number, while the pronouns distinguish anani (singular) from anoka (plural) Nakagawa (2024: 174–179, 254–256). The crossed mismatches — singular verb with plural pronoun in Horobetsu, plural verb with singular pronoun in Shizunai — confirm that the fourth-person form-set is not simply a plural of the first person, and they supply evidence for the historically composite character of the series ‹consensus›.

70.5 Shizunai ci and Sakhalin =hci: position as the diagnostic

Shizunai uses an outer ci where Saru, Chitose, and Ishikari use outer pa. The position is the same: Shizunai ci follows the person-inflected form, outside =an, in exactly the outer-plural slot Nakagawa (2024: 151–155).

Horobetsu presents a formally different element. Its -ci suffix appears fossilized in items such as iki-ci and kar-ici, and the diagnostic ordering places it inside the person marker (iki-ci=as), with the derivational layer rather than the outer plural slot. The Horobetsu form therefore behaves like a root-level suffix, not like the outer elements of Shizunai or Saru Nakagawa (2024: 154–155).

The Sakhalin form =(a)hci (Aniwa Bay =(a)hsi) was described by Murasaki as an optional third-person plural marker Murasaki (1979: 49–52). Nakagawa disputes the classification: the element is non-obligatory and appears with subjects of all persons, placing it with the outer-auxiliary set rather than with person-agreement affixes Nakagawa (2024: 151–155, 178) ‹contested›. Sakaguchi applies formal positional diagnostics and arrives at the same result: =hci attaches to the person-inflected verb, can follow an auxiliary, and precedes a nominalizer — the signature of a clitic over the person-inflected form, not a root-level agreement suffix Sakaguchi (2024: 77–83, 163). Baek adds that Sakhalin -(a)hci extends to the nominal domain, a trait shared with Uilta and Nivkh in the Sakhalin area and absent from Hokkaido Baek (2021: 73).

The result for Hokkaido is that no dialect has a productive third-person plural agreement suffix. Plural participant reference is encoded at the verbal-number layer — suppletive stems, inner -pa, outer pa or ci — and through the number mismatches of the fourth-person row, not through an additional person-affix position Nakagawa (2024: 151–155).

70.6 Multiple plural marking

The plural exponents occupy different layers of the verb and can therefore accumulate within a single predicate. A V/-pa stem encodes plural at the root level; outer pa can follow the person-inflected form of that same stem to mark additional participant or event plurality at the outer layer. Similarly, a V/-pa stem combines with causative morphology before the person affix while outer pa appears outside. In clause chains, outer pa may repeat on successive predicates because its scope is over the person-inflected predicate rather than the clause sequence as a unit Nakagawa (2024: 156–159).

Plural accumulation does not affect the cap on person affixes. A finite verb carries at most one subject index and one object index, and no third argument is indexed by person. In ditransitives such as kore 'give', plural morphology can co-occur with the ordinary object-indexing pattern in which the object affix tracks the human recipient while the theme remains an unindexed bare noun phrase Satō (2008: 147); Satō (2023: 39, 47). The two-affix cap and the ditransitive pattern are treated in Chapter 66 (Object Indexing: Monotransitive and Ditransitive Clauses) and Chapter 69 (The Personal-Affix Template: Position Classes and Affix Ordering).