Creation of English and Hindi Verb Hierarchies and their Application to Hindi WordNet Building and English-Hindi MT Debasri Chakrabarti, Gajanan Krishna Rane, Pushpak Bhattacharyya. Computer Science and Engineering Department, Indian Institute of Technology, Bombay, Mumbai, 40076, India. debasri,gkrane,pb@cse.iitb.ac.in 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Introduction Verb hierarchy System is based on creation of the verb hierarchy for English and Hindi verbs. organized according to semantics and syntax semantic hierarchy - through the super-ordinate terms and the inbuilt ontology of the UNL KB. syntactic information- through UNL case relations System is based on English verb classes and their alternation (Levin) UNL System: UW Manual, Knowledge base (KB) & specification Semantic relations of English WordNet 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Levin’s Class of English verbs Classification of the English verbs Adopted from English Verb Classes and Alternation of Beth Levin. Details of Levin’s work Levin’s classification of the English verb is the most significant and celebrated work. Assumption underlying Levin’s work Syntactic behavior of a verb is semantically determined Levin investigated and exploited this hypothesis for about 3200 English verbs. 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Details of Levin’s work Verb Classes Preliminary Investigation considerable correlation between some facets of the semantics of verbs and their syntactic behavior 200 semantic classes defined in Levin’s system each class share a number of alternations Example of verb classes verbs of putting , verbs of communication, correspond verbs etc. 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

The Universal Networking Language (UNL) electronic language for computers to express and exchange information. UNL system consists Universal words (UW) : Vocabulary of UNL Relations, attributes : Syntax of UNL UNL knowledge base (KB): Semantics of UNL 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

The Universal Networking Language UNL represents information sentence-by-sentence as a hyper-graph concepts as nodes and relations as arcs Sentence is a hyper-graph a node in the structure can itself be a graph the node is called a compound word (CW) 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Graphical representation in UNL @ entry @ present eat (icl>do) agt obj ins John (iof>person) rice (icl>food) spoon (icl>artifact) John eats rice with a spoon 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Verbal Concepts in UNL Verbal concepts in the UNL system are organized into three categories (icl>do) for defining the concept of an event which is caused by something or someone change (icl>do) : as in She changed the dress (icl>occur) for defining the concept of an event that happens of its own accord change (icl>occur) : as in The weather will change (icl>be) for defining the concept of a state verb remember (icl>be) : as in Do you remember me? 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Verbal Concepts in UNL Partial hierarchical structure for do do(agt>thing{,^gol>thing,icl>do,^obj>thing,^ptn>thing,^src>thing}) do(agt>volitional thing{,icl>do(agt>thing)}) do(agt>living thing{,icl>do(agt>volitional thing)}) do(agt>human{>living thing,icl>do(agt>living thing)}) do(agt>thing,gol>thing{,icl>do, ^obj>thing,^ptn>thing,^src>thing}) Partial hierarchical structure for do 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

do in UNL KB Semantic hierarchy in terms of the inbuilt ontology in KB do(agt>thing,gol>thing{,icl>do},obj>thing{,^ptn>thing,^src>thing}) do({icl>do(}agt>thing{,gol>thing,obj>thing)},gol>abstract thing,obj>abstract thing) do({icl>do(}agt>thing{,gol>abstract thing,obj>abstract thing)},gol>custom{>abstract thing},ob j>custom{>abstract thing}) do(gol>thing) do(gol>abstract thing) do(gol>custom) 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Creation of the verb hierarchy First, a particular verb class is selected from Levin. Next the class is categorized according to the UNL format Parent node of a class is obtained through English wordnet and various dictionaries 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Creation of the verb hierarchy “put” ‘Put your clothes in the cupboard’. (to put something into a certain place) (icl>move(agt>person,obj>concrete thing,gol>place) (loc_prep{in/on/into/under/over}) [VTRANS, VOA-ACT] “hang” ‘He hanged the wallpaper on the wall’. (to suspend or fasten something so that it is held up from above and not supported from below) (icl>put{>move}(agt>person,obj>concrete thing,gol>place) (loc_prep{from/on}) Partial hierarchy of the put class 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Verb Hierarchy in Hindi रखना ; rakhanaa; r«kHna ‘put’ ‘Put your things here.’ (to put something into a certain place) (icl>act(agt>person,obj>concrete thing,gol>place) अपना सामान यहाँ पर रखो।; («pna saman y«ha) p«r r«kHo) ; apanaa saamaana yahaa par rakho) {(adv_plc (यहाँ/वहाँ / ‘y«ha) / v«ha)’ loc_postp (पर ‘p«r’)} रखना, सजाना ; r«kHna, s«jana; rakhanaa , sajaanaa; ‘arrange’ ‘he arranged the books here’.(to put into a proper or systematic manner) (icl>put{>act}(agt>person,obj>thing) उसने किताबों को यहाँ पर सजाकर रखा। usne kitabo) ko y«ha) p«r s«jak«r r«kHa.) (usne kitabo ko yahaa par sajaakar rakhaa.) {(adv_man (सजाकर, s«jak«r ;क्रम से, kr«m se))+ (adv_plc (यहाँ/वहाँ / ‘y«ha) / v«ha)’ ))+ loc_postp( पर ‘p«r’)} 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Verb Hierarchy in Hindi Syntax frames specified for the put class in English (adv_plc{here/there}) (loc_prep) Sentence frames for put in Hindi adv_man adv_plc + adv_man loc_postp + adv_man English Hindi adv_plc (here / there) adv_man (सजाकर, s«jak«r; क्रम से, kr«m se etc ) loc_prep (in, inside, on etc) adv_plc(यहाँ/वहाँ / ‘y«ha) / v«ha)’) +loc_postp(पर ‘p«r)+adv_man (सजाकर, s«jak«r ;क्रम से, kr«m se etc) loc_postp(के उपर, ke up«r etc)+adv_man (सजाकर, s«jak«r etc) 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Verb hierarchy and the Hindi WordNet Application of the hierarchy in the Hindi wordnet will help in determining semantic relations like hypernymy and troponymy syntactic frames revealed facts like difference in the representations for troponyms in Hindi and English reclassifications of the verbs in Hindi 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Representations of Troponyms English sentence Hindi put put your things here. रखना r«kHna अपना सामान यहाँ पर रखो।; («pna s«man y«ha) p«r r«kHo) pile pile your books up on the shelves. ----- उसने खाने में एक के ऊपर एक सामान रखा।;((((((usne kHane me) ek ke Up«r ek saman r«kHa) cram she cram the books into the suitcase. उसने बक्से के अन्दर सारी किताब ठूँसकर रखी।;(usne bakse ke a)d«r sari kitab tHu)sak«r r«kHI)) 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Classification of Hindi Verbs simple compound noun + verb Verbs adjective + verb adverb + verb conjunct 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Classification of the Hindi Verbs Simple verbs खाना(kHana) ‘to eat’ Compound verbs गिर पड़ना(gir p«êna) ‘to fall down’ Conjunct verbs noun + verb आरंभ करना (ar«mbH k«rna) ‘to start’ adjective +verb शांत करना (Sant k«rna) ‘to calm down’ adverb + verb उठाकर रखना (utak«r r«kHna) ‘to lift’ 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Reclassification of the Hindi verbs Sentence frames of the verbs reveals only noun+ verb conjunct is a true conjunct Hence, a re-classification of the verbs is needed 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Application in NLP The application of the verb hierarchy in NLP gives semantic hierarchy of a verbal concept enumerates syntactic details of a verb UNL based MT will be immensely benefited possible UNL relations that appear with a concept is specified 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Application in MT Verb Sentence Frame UNL Relations fight Sam and Sue fought. conj_and agt>person Sam was fighting with Sue. prep_accompaniment{with} agt>person, ptn>person The tribesmen fought each other. -prep_with agt>person, obj>person 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY

Conclusion System statistics approximately 3000 English verbs approximately 5500 UWs Common English verbs are dealt with tested against British National Corpus Coverage of both English and Hindi verbs is increasing everyday Visualizer and an application programming interface for the verb knowledge bases in both the languages are under construction 2/2/2019 C.F.I.L.T., I.I.T. BOMBAY