This article describes possibilities of using OntoLex as a model for creating an ontology of morpho-syntactic properties of the Russian language. For this purpose we analysed morpho-syntactic properties of Russian, given in LexInfo and then extended it with grammatical categories that are not represented or that are not correctly defined in LexInfo. The introduced supplements and adjustments enable LexInfo to represent morpho-syntactic properties of the Russian language more completely and to use it for creating the OntologyBased Dictionary of Russian Grammatical Forms (OntoRuGrammaForm). The created ontology-based dictionary helps to detect grammatical forms of widely used Russian words.
The ontological approach to representation of natural language properties is currently
being developed in computational linguistics, mainly in researching natural language
processing. On the Semantic Web there are various ontology-based lexical and
semantic datasets, e.g. WordNet [
On the Semantic Web there exist ontological models representing linguistic Linked
Data that describe morphological features of languages to some extent, including
Russian, e.g. OliA [
The idea of connecting words with concepts, including the morpho-syntactic level,
which makes it possible to clarify the meaning, e.g. of polysemantic and
homonymous words, is implemented in LexInfo. In this project we used LexInfo as the most
complete ontology based on RDF model for labeling the Ontology-Based Dictionary
of Russian Grammatical Forms due to its evident advantages: separation and
independence between the ontological and linguistic levels; structuring linguistic
information; the ability to specify the meaning of linguistic constructions with respect to
arbitrary ontologies, etc. [
The goal of this project is to create an ontology-based dictionary that represents morpho-syntactic properties of the Russian language. To achieve this goal we set and consecutively resolved the following tasks: 1) analysing grammatical classes and properties of Russian, given in LexInfo; 2) collating the composition of grammatical classes and properties in LexInfo with Russian grammar books and dictionaries; 3) supplementing LexInfo with insufficient and refined Russian grammatical categories; 4) translating labels into Russian and supplying LexInfo and OntoLex elements with Russian commentaries; 5) creating the Ontology-Based Dictionary of Russian Grammatical Forms.
Both LexInfo and OntoLex were used to create the Ontology-Based Dictionary of Russian Grammatical Forms. Grammatical categories of words were determined with LexInfo, while entities/concepts in a dictionary entry were related with OntoLex.
LexInfo is a universal multipurpose model for representing morpho-syntactic properties of highly inflected languages that have genetic and typological resemblances at the level of common affixes, roots, and a regular phonetic correspondence of sounds. In general, morpho-syntactic properties of Russian can be represented in LexInfo. Nevertheless, the accomplished analysis of its structure showed that these properties are not fully represented. This fact gave rise to the intent of adjusting these properties, listed in LexInfo, in accordance with the state-of-the-art of grammar of the Russian literary language. 1 http://linguistics.okfn.org/llod 2 http://wals.info 3 https://en.wiktionary.org/wiki
The analysis of the list of Russian grammatical properties in LexInfo and its
collation with the data of academic grammar books [
The analysis of LexInfo showed that nominations of some Russian grammatical categories should be introduced (see Table 1): (1) In LexInfo the individual participle is put into the class VerbFormMood. In our view, it should also belong to the class PartOfSpeech. So, we introduced the new class ParticiplePOS, into which the individual participle is placed. (2) To the class ParticiplePOS we added the new individual shortParticiple.
The distinction between a short participle and a participle is essential for the system of the Russian language as these two forms have different inflections and different syntactical functions. (3) In LexInfo there is no individual gerund. We believe it should be added to identify the adverbial participle (the Russian gerund) as the part of speech in Russian. We introduced the new class GerundPOS, into which the individual gerund is put, and we also stated that the individual gerund belongs to the class VerbFormMood. (4) We added the individuals singulariaTantum, pluraliaTantum, fixedNumber to the existing class Number. (5) We added the new class Finiteness with two individuals – finite and nonFinite – to the class MorphosyntacticProperty. (6) We introduced the class Reflexivity with two individuals – reflexive and nonReflexive into the class MorphosyntacticProperty. (7) The individual impersonalVerb is added to the class VerbPOS. (8) The individual shortAdjective is added to the class AdjectivePOS. (9) The individual relativeAdjective is added to the class AdjectivePOS. (10)The individual collectiveNumeral is added to the class NumeralPOS.
The supplementation of grammatical categories of the Russian language in LexInfo is also connected with eliminating inaccuracies in placing grammatical categories into classes (see Table 1): (1) In LexInfo comparative is the individual of the class Degree. In our view, it is also the individual of the class AdjectivePOS. (2) In LexInfo the individual infinitive belongs to the class VerbFormMood. In our view, it also belongs to the class VerbPOS. (3) In LexInfo the individual ordinalAdjective belongs to the class AdjectivePOS. According to the grammatical properties of Russian this individual also belongs to the class NumeralPOS.
Another important supplement to grammatical properties of Russian in LexInfo is adjusting translations of class and individual labels into Russian. Some examples of this type of supplements are given below: (1) The term gerundive, which is put into the class VerbFormMood, is not accurately translated into Russian. In Latin the gerundive is a verbal adjective while the gerund is a verbal noun both in Latin and in English. In Russian the grammatical category of a gerund does not exist. We suggested introducing the individual gerundPOS to label the adverbial participle (the Russian gerund) as the part of speech. (2) In Russian there exist cardinal numerals and ordinal numerals. In LexInfo the Russian labels for the individuals cardinalNumeral and ordinalNumeral from the class NumeralPOS are confused and should be interchanged. (3) In LexInfo class Finiteness from the class MorphosyntacticProperty is labeled inaccurately in Russian. Our suggestion is to supply the grammatical category of finiteness as well as the class Finiteness by the Russian label spryagaemost. As the English conjugation and the Russian spryagaemost are quasi-synonyms, we find the LexInfo label Finiteness appropriate to indicate the ability of Russian verbs to conjugate.
In any subject area the connection of words with concepts in the form of an ontology should be based on a morpho-syntactic level. The idea turned out to be fruitful for creation of OntoRuGrammaForm. The completed experimental work made it possible to connect words with concepts by implementing morpho-syntactic properties of the Russian language. 3.1
With the additions and adjustments, introduced into LexInfo, it became possible to represent morpho-syntactic properties of Russian more completely and accurately in the Ontology-Based Dictionary (OntoRuGrammaForm). The ontology is aimed at revealing grammatical forms for the Russian words in general use.
The Ontology-Based Dictionary of Russian Grammatical Forms (OntoRuGrammaForm) contains 389,226 lemmas and 5,097,173 word forms. It is available for public use at http://ldf.kloud.one/ontorugrammaform. The experience of creating the dictionary can be used for educational purposes, e.g. teaching Russian and testing knowledge of Russian. 3.2 the Web
The Open Corpora4, the open corpus of the Russian language, was used as a source for OntoRuGrammaForm. The Open Corpora is compiled by volunteers using web texts and is available in XML and plaintext formats. The Open Corpora XML schema can be viewed at http://opencorpora.org/export/dict/dict.opcorpora.xsd.
The programme component of the dictionary is written in JavaScript (NodeJS), as we hold to the idea of creating and selecting the components to work with ontologies on this particular stack of technologies. We divided the technical implementation process into three blocks for convenience: 1) automatic conversion of the Open Corpora labels into the OntoLex labels; 2) for the backend we used Linked Data Fragments5; 3) the client part is under development.
The automatic conversion of the Open Corpora labels into the OntoLex labels is a 1:1 mapping. The project of label conversion is available at https://github.com/cnstntn-kndrtv/opencorpora2ontolex.
The structure of OntoRuGrammaForm conforms to the Lexicon Model for
Ontologies, given in Morpho-Syntactic Description section of Community Report6. As an
example we use the Russian polysemantic word ‘ёж’ (‘yozh’) – ‘hedgehog’ [
The description of the word, lemma, and word form relation of the word ‘ёж’ (‘yozh’) – ‘hedgehog’ in the first meaning in the Turtle format comes further. 4 http://opencorpora.org 5 http://linkeddatafragments.org 6 https://www.w3.org/2016/05/ontolex/#morphosyntactic-description # :1_yozh ёж :1_yozh a ontolex:Word ; ontolex:canonicalForm :1_yozh:lemma ; ontolex:otherForm :1_yozh:form1_yozh, :1_yozh:form2_ezha, :1_yozh:form3_ezhu . # :1_yozh ёж Lemma :1_yozh:lemma ontolex:writtenRep "ёж"@ru ; lexinfo:partOfSpeech lexinfo:noun ; lexinfo:animacy lexinfo:animate ; lexinfo:gender lexinfo:masculine . # :1_yozh ёж Forms :1_yozh:form1_yozh ontolex:writtenRep "ёж"@ru ; lexinfo:number lexinfo:singular ; lexinfo:case lexinfo:nominativeCase . :1_yozh:form2_ezha ontolex:writtenRep "ежа"@ru ; lexinfo:number lexinfo:singular ; lexinfo:case lexinfo:genitiveCase . :1_yozh:form3_ezhu ontolex:writtenRep "ежу"@ru ; lexinfo:number lexinfo:singular ; lexinfo:case lexinfo:dativeCase .
As a result of our research, we supplemented and adjusted LexInfo for the adequate description of morpho-syntactic properties of the Russian language. These supplements and adjustments are proposed as an extension to LexInfo for Russian. The supplemented and adjusted grammatical properties of Russian in LexInfo made it possible to create the Ontology-Based Dictionary of Russian Grammatical Forms (OntoRuGrammaForm) which is aimed at revealing grammatical forms of widely used Russian words. Further work will involve modeling syntactical structure of sentences with LexInfo to create a system of connecting natural language with concepts in ontologies. We also plan to create client applications for queries into OntoRuGrammaForm.
The authors are grateful to Telephone Systems Ltd for support and technical assistance as a part of kloud.one project.