Verbs and Grammar
Compound verbs, auxiliaries, and particles have different boundary rules. These examples show which expressions stay whole and which retain their grammatical parts, including colloquial and classical forms.
All examples use the comparison baseline. For labels on the same tokens, see POS Classification.
Verbs and auxiliaries
Compound Verbs
Verb stems in 連用形 followed by subsidiary verbs are merged into compound verbs.
Supported V2 elements include: 込む, 出す, 続く, 返す, 合う, 直す, 切る, 上がる, 抜く, こもる, 続ける, つける, 替える, 合わせる, 上げる, 下げる, 掛ける, 入れる, etc. (300+ kanji and kana forms)
Grammaticalized subsidiaries such as 過ぎる and かねる are deliberately not merged — see Subsidiary Auxiliary Splitting.
Desiderative たがる
The desiderative-observation auxiliary たがる, including its inflected forms, is kept as a single auxiliary token.
Subsidiary Auxiliary Splitting
Grammaticalized subsidiary verbs — 過ぎる (excess), かねる (inability), そびれる (missed chance), 尽くす (exhaustive) — split off from the main verb. Suzume records their auxiliary role in the extended POS; the public POS remains VERB for the 過ぎる forms and is AUX for the other subsidiary forms below. MeCab's own treatment varies with the dictionary: some combinations come out merged (飲み過ぎ), others split with the 非自立 subcategory.
Pejorative やがる
The pejorative auxiliary やがる stays whole after a verb continuative. The IPA dictionary splits this form into parts of やる and がる; Suzume assigns the auxiliary its own lemma and AUX_卑罵 subtype.
Negative ずに
The negative auxiliary ず and the following particle に remain separate, preserving the grammatical boundary.
Productive Negative Splitting
Unlike the closed nai-adjective word list, productive "stem + ない" combinations split, keeping the stem searchable.
Classical and Literary Endings
Classical inflections keep the same grammatical boundaries as their modern counterparts. The supported families include negative forms, conjectural and obligation auxiliaries, past and perfect auxiliaries, prohibitives, and imperatives. A compact sample:
- Classical negative ぬ splits from the 未然形: 知らぬ → 知ら + ぬ (
AUX) - Literary volitional ん splits the same way: 乗り越えん → 乗り越え + ん (
AUX) - Classical past き keeps its own auxiliary boundary: 行かざりき → 行か + ざり + き
The conjectural らむ follows a terminal verb form. Suzume retains that verb boundary where the IPA dictionary reads a different noun–verb pair:
Classical adjective continuatives such as 美しかり keep their inflection together and their modern lemma. The following けり remains a separate past auxiliary:
Colloquial Auxiliary Forms
Past conjectural, fused desiderative, and volitional forms retain their auxiliary boundaries:
| Input | Suzume |
|---|---|
| 食べたろう | 食べ(VERB) / たろ(AUX, lemma: た) / う(AUX) |
| 食べてえ | 食べ(VERB) / てえ(AUX, lemma: たい) |
| いこう | いこ(VERB, lemma: いく) / う(AUX) |
| ゆこう | ゆこ(VERB, lemma: ゆく) / う(AUX) |
Function words and grammatical boundaries
Closed Compound Particles
Closed expressions that function as one particle are kept whole.
The selected IPA dictionary already emits expressions such as と共に and, in some contexts, につれて as one token, so they are not boundary differences in this baseline. Other dictionaries may split them.
Fixed Colloquial Function Words
Fixed function words are kept whole even when a dictionary-driven analysis fragments them.
がてら ("while, on the occasion of") is one particle, and the colloquial そんなら ("in that case") is one conjunction.
Productive Function-Word Chains
Suzume preserves the internal verb and particle boundaries of productive constructions instead of treating the whole spelling as a fixed function word.
The same rule gives を / もっ / て for をもって. Closed expressions with no productive verb boundary remain whole, as in や否や.
The quotative って also remains a separate particle after a clause-final particle: 行くかって becomes 行く(VERB) / か(PARTICLE) / って(PARTICLE).
Adverbial Noun + Particle
Some sequences that the selected dictionary lexicalizes as one function word are kept as noun + particle.
Leading Fixed Units
The determiner わが is split from the following noun.
お/ご Prefixes
Suzume splits お/ご honorific prefixes from nouns but keeps them merged when they form inseparable lexemes.
split — separable prefix
Suzume keeps these lexical exceptions whole: お金, お前, おかず, おでん, おもちゃ, おすすめ, おいら, おっさん, お疲れ様, おいで, and family terms (お母さん, お父さん, お兄ちゃん, お姉さん, おじさん, おばさん, おじいさん, おばあさん, etc.). The selected MeCab baseline keeps many of them whole but splits お兄ちゃん and お姉さん after お.
Tari-Adverbs
Tari-conjugation adverb stems followed by と are merged into a single adverb.
Applies to: 泰然, 堂々, 悠々, 淡々, 粛々, 颯爽, 毅然, 漫然, 茫然, 呆然, 唖然, 愕然, 断然, 歴然, 整然, 雑然, 騒然, 憮然, 黙然, 昂然, 厳然
Kango + として
For fixed tari-adverb constructions such as 依然として, MeCab treats the expression as one adverb. Suzume splits the adverb form from the する conjugation. Productive expressions such as 名詞として already have grammatical boundaries in both analyzers.
Predicates and pronouns
Copula Negation
After a nominal predicate, Suzume treats じゃ as the copula and ない as the adjective. The nominal host is part of the comparison so the copular context is explicit.
Causative-Passive
MeCab sometimes merges godan verb 未然形 + causative さ into one token. Suzume normalizes this inconsistency.
Formal Noun ふう
ふうに after a demonstrative determiner is split into its grammatical determiner, formal-noun, and particle units.
Indefinite か
The indefinite particle か is split from an interrogative pronoun. A following existential いる is then treated as a main verb.