American Journal Of Philological Sciences
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VOLUME
Vol.05 Issue07 2025
PAGE NO.
25-29
10.37547/ajps/Volume05Issue07-07
Towards A Unified Structural Theory of Parts of Speech
in Modern Linguistics
Ikramjon Abdullayev
PhD student., Department of English and Literature, Andijan State Institute of Foreign Languages, Andijan, 170126, Uzbekistan
Received:
15 May 2025;
Accepted:
11 June 2025;
Published:
13 July 2025
Abstract:
This paper presents a unified structural theory of parts of speech, integrating comparative evidence
from English, Uzbek, and Russian. It addresses the longstanding debate on word-class categorization by combining
distributional, syntactic, morphological, and semantic criteria into a comprehensive framework. Utilizing
descriptive grammars and typological studies, we identify universally communicative "primary" parts of speech
common across these languages, alongside "secondary" categories specific to individual linguistic structures. Our
analysis emphasizes the importance of clearly distinguishing semantic and formal criteria to avoid theoretical
ambiguity. The unified model effectively accounts for cross-linguistic variations, such as differing usage of articles,
pronoun case systems, and morphological distinctions, ensuring theoretical coherence.
Keywords
: Parts of speech, structural linguistics, linguistic universals, unique characteristics, systemic-structural
analysis, language theory.
Introduction:
The classification of words into parts of
speech remains a contentious issue in linguistics,
unresolved despite extensive historical examination.
Traditionally, grammarians identified parts of speech
primarily through semantic (meaning-based), syntactic
(sentence-function-based), and morphological (form-
based) criteria. This multiplicity
—
exemplified by the
Western classical tradition, which inconsistently
recognized categories like articles and adjectives
—
illustrates the challenge in universally defining parts of
speech.
Modern structural linguistics defines parts of speech by
their distribution and syntactic behavior within
grammatical systems. Charles C. Fries (1952) notably
categorized English words based on their distributional
positions, marking a significant shift away from
semantic criteria [4.118-119]. However, purely formal
classifications often fail to capture cross-linguistic
nuances. Christian Lehmann highlights the essential
independence and intersection of semantic and
structural aspects, shaped significantly by historical and
cultural factors, resulting in language-specific systems
[11.123].
Universally, languages distinguish core categories
—
primarily nouns (reference to entities) and verbs
(predication of actions or states)
—
but other categories
like adjectives and adverbs vary widely. While English
clearly marks adjectives as a separate class, many
languages merge their function with nouns or verbs
[2.53].
This article proposes a unified structural theory by
systematically comparing parts-of-speech systems in
English, Russian, and Uzbek. These languages illustrate
diverse structural realizations of universal functions,
providing
a
comprehensive
framework
for
understanding both universal elements and language-
specific distinctions. Our comparative approach aims to
enhance theoretical coherence within linguistic
typology and the broader theory of language.
METHODS
This study uses descriptive grammars and linguistic
resources for English, Russian, and Uzbek. For English,
sources include structuralist descriptions by B. A. Ilyish
[8.5] and comprehensive grammars by Quirk et al.
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(1985) [12.67]. For Russian, cognitive-semantic
analyses by E. S. Kubryakova [10.33] and standard
Russian grammars [18.37-40] were used. Uzbek
materials include Uzbek Grammar, Vol. I: Morphology
(1995) [13.25] and comparative typology lectures by G.
M. Hoshimov [7.5]. Additionally, typological studies
highlighting isomorphic (shared) and allomorphic
(language-specific) features (Jalalova, 2023 [9.49-52])
and seminal works by Fries (1952) [4.118], Hockett
(1958), Croft (1991), and Baker (2003) were integrated
into the theoretical framework.
The research employs comparative structural analysis,
considering three criteria: semantic (meaning),
morphological
(inflectional
and
derivational
properties), and syntactic (sentence function) [12.136-
137]. Each language’s part
-of-speech system was
analyzed to identify common and distinctive features,
focusing on isomorphic elements (e.g., universally
distinguished nouns and verbs [5.75]) and allomorphic
elements (e.g., presence or absence of articles [4.251-
254]). The analysis included: (1) descriptive alignment
of each language’s categories, (2) structural synthesis
informed by Baker’s (2003) formal syntactic criteria
[1.68] and
Croft’s
(1991)
functional
-cognitive
continuum [2.169], and (3) theoretical modeling to
propose
a
unified
classification
framework.
Interpretive discussion accompanied the analysis,
ensuring both theoretical coherence and empirical
validity.
RESULTS AND DISCUSSION
Major Criteria for Parts of Speech: Toward an
Integrated Definition
This study addresses the challenge of defining parts of
speech by integrating semantic, morphological, and
syntactic criteria into a unified theoretical framework.
Traditional grammar offers simplistic definitions (noun
as "person, place, or thing," verb as "action or state"),
which are often insufficient. Purely formal approaches,
like Fries’ distributional method, may be too language
-
specific. An effective unified theory requires combining
semantic meaning, morphological forms, and syntactic
functions.
Nouns typically denote entities or "thingness" [12.136-
136], marked morphologically for number and case in
languages like Russian and Uzbek, and positionally by
determiners in English. Nouns universally serve as
propositional arguments (subjects or objects), although
case and number marking vary across languages [9.49-
52; 18.49-52].
Verbs universally denote predication (actions,
processes, states) and syntactically function as
predicates. They exhibit significant morphological
variability, with English relying on auxiliary verbs for
tense/aspect, while Russian and Uzbek utilize extensive
inflectional paradigms [11.197-204].
Adjectives and adverbs, considered "secondary"
categories, display greater divergence. English
adjectives are invariant and typically precede nouns;
Russian adjectives agree morphologically with nouns;
Uzbek adjectives remain invariant and often function
predicatively without copulas. A unified definition
categorizes adjectives as properties modifying nouns or
predica
tes, reflecting cognitive linguistics’ view of
adjectives as intermediate between nouns and verbs
[2.53; 7.31-34].
Functional categories like pronouns, numerals,
conjunctions, and particles differ considerably across
languages but fulfill universal grammatical roles.
Pronouns function deictically or anaphorically, while
numerals exhibit dual lexical-functional behavior.
Russian-specific categories like "words of the category
of state" highlight language-specific classifications,
accommodated by the unified theory without enforcing
universal categories.
The proposed unified theory uses a distributional
prototype approach, identifying core prototypical
instances of nouns, verbs, and adjectives, while
allowing intermediate and language-specific cases. This
model accommodates linguistic diversity and resolves
theoretical debates through an integrated definition of
parts of speech.
Comparative Analysis: English, Uzbek, and Russian
Parts of Speech
By applying the above criteria and unified perspective,
we derived a comparative overview of the parts of
speech in English, Uzbek, and Russian, summarized as
follows:
NOUN: Nouns are present in English, Russian, and
Uzbek as a robust open class. English nouns inflect
primarily for number (singular/plural) and possessive
case (-
’s), without extensive case marking or gender
distinctions. Russian nouns inflect for number, gender
(masculine, feminine, neuter), and six grammatical
cases (nominative, accusative, genitive, dative,
instrumental, locative). Uzbek nouns use suffixes for
number (e.g., kitob "book", kitoblar "books") and six
grammatical cases analogous to Russian (genitive -ning,
dative -ga, accusative -ni, locative -da, ablative -dan),
but lack gender. Each language exhibits language-
specific phenomena, such as English mass vs. count
nouns distinction, Uzbek’s broad pluralization
capability (e.g., ma’lumotlar "informations"), and
Russian’s singularia tantum and pluralia tantum (e.g.,
очки "glasses") [4.265
-273]. The unified theory
interprets these variations as language-specific
features within the noun category.
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PRONOUN: Pronouns differ significantly among the
languages studied. English pronouns have a simplified
two-case system (he/him), while Uzbek pronouns
mirror noun declensions with six cases (men "I", meni
"me", menga "to me"). Russian pronouns exhibit
complex and irregular declensions (я/меня/мне).
English distinguishes gender in third person singular
(he, she), Russian distinguishes gender across third
person pronouns (он, она), while Uzbek does not
differentiate by gender. The unified theory categorizes
pronouns structurally as noun-substitutes, highlighting
their deictic and anaphoric functions [9.49-52].
VERB: Verbs universally denote actions, states, or
events, functioning syntactically as predicates. English
verbs employ auxiliaries (will, have, be) and minimal
inflectional morphology (run/ran), whereas Russian
verbs extensively inflect for person, number, tense,
aspect, mood, and gender (бежать, бежал). Uzbek
verbs use agglutinative suffixation indicating tense,
mood, and person (bor-di-m "I went"). Despite
morphological variation, verbs in all three languages
share a common structural core: predication and
thematic role assignment to noun phrases. Thus, the
unified theory emphasizes verbs' predicate role,
accommodating
cross-linguistic
morphological
diversity as parameterized expressions of universal
tense/aspect/mood functions [11.197-204].
ADJECTIVE: Adjectives differ considerably across
languages. English adjectives typically do not inflect
and occupy fixed syntactic positions before nouns or
after copulas. Russian adjectives inflect extensively for
gender, number, and case, aligning with nouns
(большой дом, большая комната). Uzbek adjectives
remain invariant (katta uy, katta xona) and often
function predicatively without copulas (Havo issiq). The
unified theory categorizes adjectives as words denoting
properties that structurally modify nouns or predicate
complements, acknowledging their intermediate
semantic and syntactic status between nouns and
verbs [2.53; 7.31-34].
ADVERB:
Adverbs
across
languages
form
heterogeneous classes indicating manner, time, place,
and degree. English primarily uses the morphological
marker -ly (quickly), Russian uses suffixes -o or -e
(быстро), and Uzbek relies largely on contex
tual cues,
with many adverbs identical to adjectives (yaxshi
"good/well"). The unified theory defines adverbs
functionally, as modifiers of predicates, adjectives, or
clauses,
recognizing
significant
cross-linguistic
variability and context-dependent usage [11.153-158].
OTHER CATEGORIES: Conjunctions (English: and, or,
but; Russian: и, или, но; Uzbek: va, yoki, lekin),
prepositions/postpositions (English: in, to, by; Russian:
в, к, через; Uzbek: bilan "with", uchun "for"), particles
(English: no, indeed, even; Russian: -
то, же; Uzbek: mi
for questions, -ku for emphasis), and interjections
(English: oh, wow; Russian: ой, ну; Uzbek: voy, mana)
are present across English, Russian, and Uzbek, though
categorized and utilized differently. These constitute
closed-class items primarily serving grammatical or
pragmatic functions.
Uzbek features a diverse array of modal particles (e.g.,
albatta "certainly", balki "perhaps"), occasionally
classified separately. English and Russian similarly have
modal words (English: pe
rhaps, indeed; Russian: может
быть "maybe", конечно "of course"), often variably
classified as adverbs or particles. Minor categories
beyond nouns, verbs, adjectives, and adverbs differ
among languages, such as Russian’s "category of state"
words, Uzbek’s
distinct postposition classification, and
English’s traditional separation of articles as a part of
speech.
Our unified theory treats these minor classes as
functional categories
—
closed-class elements signaling
grammatical relationships or speaker attitudes rather
than lexical content. It groups prepositions,
postpositions,
and
case-marking
clitics
under
"relational markers," emphasizing their semantic
relational roles (location, instrument, etc.) rather than
their formal status as independent words or affixes
[4.251-254].
Coordinating
and
subordinating
conjunctions are similarly viewed as language-specific
manifestations of universal logical relations.
This approach aligns conceptually with Baker’s (2003)
distinction between lexical categories (nouns, verbs,
adjectives) and functional categories (determiners,
complementizers, etc.) [1.68]. While agnostic to
specific generative models, our theory supports this
fundamental
lexical
vs.
functional
division,
acknowledging
cross-linguistic
variations
in
classification practices.
Toward a Unified Structural Theory
This research proposes a unified structural theory of
parts of speech based on comparative evidence from
English, Russian, and Uzbek, outlining several key
principles:
Universality of Core Functions: Every human language
requires basic communicative functions, notably
reference (nouns) and predication (verbs). Our theory
begins with these universal functions, viewing other
categories (adjectives, adverbs, etc.) as specialized
expansions around these core roles.
Language-Specific Category Structures: While nouns
and verbs are near-universal, categories like adjectives
or adverbs depend on language-specific structures and
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semantic
distinctions.
The
theory
recognizes
conditional universality, meaning all languages perform
similar functions but map these differently onto lexical
categories [11.182-190].
Structural Criteria as the Basis: Parts of speech are
defined primarily through structural properties
(distributional, syntactic, morphological). For instance,
adjectives differ structurally across English (pre-
nominal, no inflection), Russian (gender, number, case
agreement), and Uzbek (invariant form, predicative use
without copula). Thus, our unified approach
emphasizes structural criteria, acknowledging cross-
linguistic variation [4.118-119].
Semantic Prototype Alignment: The theory employs
semantic prototypes, where categories have central,
prototypical meanings but also include peripheral
members (e.g., event nouns, stative verbs). This
approach accommodates lexical ambiguity and fuzzy
category boundaries, reflecting cognitive linguistic
insights and human categorization processes.
Comparative Insights
–
Isomorphic vs Allomorphic
Features: Our
comparative
analysis
identifies
isomorphic features common to all languages studied
(noun/verb distinction, pronouns, conjunctions) and
allomorphic, language-specific features (English
articles, Russian case, Uzbek postpositions) [4.251-
254]. The theory incorporates these differences by
emphasizing universal functional roles while allowing
language-specific realization.
Theoretical Synthesis: The unified structural theory
operates on two levels:
Level 1: Universal Functional Categories
–
abstract roles
like Referential, Predicative, Attributive, Modifying,
and Linking.
Level 2: Language-Specific Lexico-Grammatical Classes
–
actual parts of speech in each language (nouns, verbs,
adjectives,
etc.),
reflecting
specific
structural
implementations of these universal functions.
Implications and Original Insights: Our unified theory
aids comparative linguistics and language education by
clarifying cross-linguistic differences (e.g., article use in
English vs Uzbek, verb aspect in Russian vs English). It
balances structural and cognitive perspectives,
emphasizing that categories emerge from structural
constraints and historical development rather than
purely cognitive motivations [11.143-151].
Overall, the unified theory provides a coherent
framework accommodating linguistic diversity and
universal principles, offering practical implications for
linguistic theory and pedagogy, and enhancing cross-
linguistic understanding.
CONCLUSIONS
In conclusion, this study presents a unified structural
theory of parts of speech, highlighting its applicability
to English, Uzbek, and Russian. Our analysis
demonstrates several key contributions:
We established that typologically diverse languages can
be analyzed within a unified structural framework,
highlighting nouns and verbs as universal core
categories. Secondary categories (adjectives, adverbs,
etc.) exhibit more language-specific traits but remain
comparable through shared functional criteria.
Our theory integrates semantic, morphological, and
syntactic criteria into a cohesive definition of parts of
speech. This multi-dimensional approach reflects
cognitive reality and avoids oversimplification,
ensuring accurate cross-linguistic comparisons.
We affirmed a hierarchical relationship, with nouns and
verbs serving as universal structural backbones, and
adjectives,
adverbs,
numerals,
and
pronouns
considered secondary or derived categories. This
structural hierarchy explains linguistic stability and
variability across languages.
By comparing English, Uzbek, and Russian, our theory
accounts for language-specific phenomena, such as
Uzbek's flexible use of adjectives as predicates and
Russian's unique "category of state." The unified
framework accommodates these anomalies by
mapping them onto universal functional roles.
Our unified structural perspective supports linguistic
education and cross-linguistic understanding, aiding
students and educators in comprehending grammatical
parallels and distinctions among English, Uzbek, and
Russian.
We emphasized language fluidity, historical evolution
of categories, and human cognitive processes, ensuring
our analysis remains engaging and reflective of human
categorization practices.
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