原田 康也

吉村 宏樹

増市 博

大熊 智子

English

Okuma, Tomoko

49819

Masuichi, Hiroshi

49820

Yoshimura, Hiroki

49821

Harada, Yasunari

49822

大熊, 智子

49816

増市, 博

49817

吉村, 宏樹

49818

原田, 康也

14168

1000080189711

Waseda University Repository

The treatment of Japanese focus particles based onLexical-Functional GrammarTomoko OHKUMACorporate Research GroupFuji Xerox Co., Ltd.430 Sakai, Nakai, AshigarakamigunKanagawa, JapanOhkuma.Tomoko@fujixerox.co.jpHiroki YOSHIMURACorporate Research GroupFuji Xerox Co., Ltd.430 Sakai, Nakai, AshigarakamigunKanagawa, JapanHiroki.Yoshimuragfujixerox.co.jpHiroshi MASUICHICorporate Research GroupFuji Xerox Co., Ltd.430 Sakai, Nakai, AshigarakamigunKanagawa, JapanHiroshi.Masuichi@fujixerox.co.jpYasunari HARADASchool of Law, Waseda University1-6-1 Nishi-waseda, Shinjuku,Tokyo, Japanharada0waseda.jpAbstractThe purpose of this paper is to discuss treatment of 'focus particles' in Japanese sen-tences to be incorporated in a Japanese parsing system based on the Lexical-FunctionalGrammar(LFG) formalism. Focus particle can follow nouns, quantifiers, verbs, otherparticles (postpositions) and auxiliary verbs. Thus, it is necessary for a large-scalegrammar to treat focus particles properly. Furthermore, there are syntactic and se-mantic ambiguities caused by the particles. We propose phrase structure rules andlexical entry constraints which cover focus particles in various positions and accountfor the ambiguities.1 IntroductionAs has been observed in many studies, various functional relations are expressed by particlesin Japanese. In particular, particles such as `kurar , `bakarr , 'clake', `nomr, `hodo' and 'made'specify focus in sentences. It has been observed that these particles mark contrastive focuswithin sentences (Numata et al., 2000). It is important for a Japanese parsing system to be ableto treat these focus particles properly, because focus particles bear different syntactic functionsdepending on where they appear in a given Japanese construction. In this paper, we proposephrase structure rules and lexical entry constraints to treat Japanese focus particles on the basisof the Lexical-Functional Grammar (LFG) formalism (Kaplan and Bresnan, 1982; Dalrymple,2001). The proposed rules and constraints for treating focus particles have been incorporatedinto a Japanese LFG system we are currently developing and have been used extensively forparsing real-world Japanese text.2 Japanese LFG systemOur Japanese LFG parsing system development aims at broad coverage and deep analysis (Ma-suichi and Ohkuma, 2003; Masuichi et al., 2003).The lexical entries for the words in the input are created by the output of the Chasen mor-phological analyzer (Matsumoto et al., 1999). In addition to these lexical entries, we have otherlexicon files for verbs, adjectives, adjectival nouns and function words.Lexical entries for verbs, adjectives and adjectival nouns were written based on the case frameinformation in the Japanese IPAL dictionary (IPA, 1987) and have been manually enhanced.448Lexical entries for verbs consist of 10,387 entries and 41,115 functional annotations for 2,366verbs. Lexical entries for adjectives and for adjectival nouns consist of 947 entries and 2,197functional annotations for 369 words in total.Lexical entries of focus particles are included in our 'core lexical entries'. Core lexical entriesinclude those for basic words such as auxiliary verbs, postpositional particles and so forth, plussyntactically important nouns such as `toki' (time) and `aida' (interval) and consist of 1,252entries and 1,913 functional annotations for 675 words.Phrase structure rules and constraints for focus particles are described in the grammar rules.The grammar rules include 2,468 terms in their disjunctive normal forms and 1,223 functionalannotations. The Japanese grammar rules have been designed in such a waty that we couldcapture cross-linguistic parallelisms (Ohkuma and Masuichi, 2002; Kim et al., 2003), which isone of the major objectives of the Parallel Grammar Project (parGram) (Butt et al., 2002).ParGram uses the parser and grammar development platform XLE for six languages: English,French, German, Norwegian, Japanese, and Urdu .XLE outputs all possible analyses of the input as c(onstituent)-structures and f(unctional)-structures. C-structure encodes phrasal dominance and precedence relations and is representedas a phrase structure tree. F-structure encodes syntactic predicate argument structure and isrepresented as an attribute-value matrix (Maxwell and Kaplan, 1993).3 Japanese focus particlesJapanese focus particles can follow nouns, quantifiers, verbs, auxiliary verbs and other particles(Numata et al., 2000). We assume they are basically classified into the four types shown in(A)-(D).(A) After nouns or quantifiers(1) kare-dake-ga Tokyo-e ik-ta.he.F.nom	 Tokyo.to go.pastOnly he went to Tokyo.(2) Kaiin-wa	 zyosei-nomi da.member.T.nom woman.F	 is.The members are only women.(3) kanozyo-wa 31co-hodo ringo-o	 taber-ta.she.Top.nom 3.parts.F apple.acc eat.pastShe ate about 3 apples.(B) After verbs (sentential clauses)(4) naku-kurai kitui sigoto da-ta.cry.F	 hard work was.It was such hard work that I almost cried.(5) Tyotto miru-dake desu.little	 look.F	 is.Just looking.(C) After auxiliary verbs(6) kanozyo-wa Tyokoreto-o taber-te-bakari-iru.she.T.nom chocolate.acc eat-particle.F.Prog.She has been just eating chocolates.449(7) oo	 sugite moter-nai-kurai-da.much too	 hold.neg.FIt is so much that someone almost can't hold it.(D) After case-marking particles(8) Kare-ni-dake-wa kono nyusu-o tutaer-tai.he.dat.F.T	 this news.acc tell.Want(I) want to tell this news only to him.(9) kare-wa	 Gakko-de-bakari hon-o	 yomu.he.Topic.nom school.Obl.F	 book.acc readHe read a book just in school.This behavior of the focus particles indicates that they have similar syntactic distribution toadverbs in English. They also have similar meanings to adverbs in English. For example, 'clake'and `nomi' can be translated as 'only' and `hodo' as 'approximately'. The following phrasestructure rules (10)-(13) simply treat focus particles as adverbs (ADJUNCTS) as in (Butt et al.,1999). Rule (10) corresponds to (A), (11) to (B), (12) to (C) and (13) to (D). These rules coverthe examples in (A)-(D).(10) N —+	 N	 FP.Ct=1) (TADJUNCT=1)(11) S	 S	 FP.(1-.1) (TADJUNCT=1)(12) AUX —4 AUX*	 FP*(IGF* ADJUNCT=1)(13) PP	 PP*	 FP*(IGF* ADJUNCT=j)4 Ambiguity of focus particlesThe rules above cannot treat the ambiguity of the sentence in (14) in which the focus particleclicurai' follows the pronoun ‘kare' (he).(14) kare-kurai eigo-o	benkyosur-ta-darou.he.F	 English.acc study.Past-mayThere are two possible interpretations of (14), as given in (15) and (16). Rule (10) inducesthe parsing result that corresponds to (16) only, and the interpretation (15) is missing.(15) He may have studied English if nobody else does.(16) Someone may have studied English as hard as he does.The same problem occurs with the focus particle 'made'. Sentence (17) has two possible inter-pretations: (18) and (19). Rule (10) induces a parsing result only for (19).(17) yusyoku-made nobir-ta.dinner.F	 postponed.Passve.Past(18) Even the dinner was postponed.(19) Something was postponed until the dinner.4505 Phrase structure rules for focus particleWe account for the phenomena shown in the examples above by taking the position that Japanesefocus particles have two distinct syntactic functions (Mizutani, 1990). The focus particles in (A)and (B) are categorized as a kind of suffix (Focus Suffix, FS) that follows nouns and verbs, whilethe focus particles in (C) and (D) are categorized as a kind of postposition (Focus PostPosition,FPP) that follows particles and auxiliary verbs. A phrase together with a following FS functionsas an adverb. Therefore, we postulate the phrase structure rule and lexical entry constraintshown in (20).(20) ADV	 { Sadj 1 Nadj}	 FS.(T==i)FS kurai (IFOCUS-FORM).'k-urarRules for FPP are shown in (21) and (22).(21) NP	 Nadj	 {E I PP I FPP}*.(T=1)FPP kurai (IFOCUS-FORM).'kurar(22) VP	 V	 {PP 1 AUXverb I FPP}*.(T.1)FPP kurai (TFOCUS-FORM)=Iurai'.In the analysis of sentences like (14), both rule (20) and rule (21) are used (invoked).When (20) is applied, our Japanese LFG system outputs the c-structure shown in Fig. 1 andthe corresponding f-structure shown in Fig. 2. This analysis corresponds to the interpretationin (15). In this analysis, `kare' (he) is the SUBJ in (14); the system interprets the focus particle`kurai' as an FPP that follows a dropped nominative case marker (E).CS 1:	 ROOTSadj PERIODI•NP	 NP	 VverbNadj PPsubj Nadj PPobj V AUXpast AUX AUXI	 I	 I	 I	 I	 I	 I	 IPRON FPP Nzero	 NMI" 4 'it	 PE 3<	 NFigure 1: c-structure for (15)451"igt < So AU 96.3irn tt. ti	 "t#341-r4 [0 :pro] ,+', CASE nom,, FOCUS-FORM < SO ' , GEND-SEM male, NUM sg, PERS 3, PRON-FORM	 PRON-TYPE perjRED pro'NIM CAS pRED 	 15FASE acc, PERS 31ADEREss (presumption?DF	 [FOCUSnominal CO:prolATNS-ASP 1400D indicative, TENSE past]PASSIVE -, STMT-TYPE decl, VTYPE mainFigure 2: f-structure for (15)When (21) is applied, our system outputs the c-structure in Fig. 3 and the correspondingf-structure shown in Fig. 4. This analysis corresponds to the interpretation in (16). In thisanalysis, 'kare' is an ADJUNCT in (14); the system interprets the focus particle lure as FSthat follows the pronoun 'kare' as a siifix. Sentence (17) is analyzed in the same way as (14).The above rules for Japanese focus particles can output two possible analyses for sentences like(14) and (17).Note that the syntactic structures represented in the c-structures shown in Fig. 1 and Fig. 3are almost the same. The semantic difference between (15) and (16) is realized in the f-structuresshown in Fig. 2 and Fig. 4.CS 2:	 ROOTSadj PERIODADVP	 NP	 Vverb/..\\	Nadj	 FS	 Nadj PPobj V AUXpast AUX AUX	I	 I	 I	 I	 I	 I	 I	 IPRON < SO Nzero ,e Nate re:	 iE 3	I	 1	fik	 NFigure 3: c-structure for (16)'4* <	 Nan JUS1-4	 •PRED	 < (11-STEC:pro), 15:M1SUB/ [PRON-TYPE nullOBJ	 S[CASE a' cc, PERSADJUNCT { PFD 'Pro'OLavV-TYTC vp-adv, ANIM +, FOCUS-FORM < 	 GEND-SEM male, NUM sg, MS 3, PRON-FORM , PRON-TYPE perADDRESS irprasumptio4TNS -ASP EIXO indicative, TENSE past]PASSIVE -, STMT-TYPE dacl, VTYPE mainPREDSUSI1111Figure 4: f-structure for (16)452Furthermore, (20)-(22) do not overgenerate analyses from unambiguous input sentences, whilethe rules account for the ambiguities caused by focus particles. When our system parses (3),(21) and (22) do not apply. Thus, our system outputs only one analysis by using (20); this isshown in Fig. 5 and Fig. 6. In other words, lodo' in (3) is interpreted as FS, but not FPP, inour analysis.CS 1:	 ROOT./\Sadj PERIODNP	 NP	 ADVP	 Vverb/\Nadj PPsubj Nadj PPobj Nadj	 FS	 V AUXpast	I	 I	 I	 I	 I	 I	PRON	 it Nzero I Nnumerical a e .ft‘?"6 'it	I	 I	fittr	 N	 NUMBER NUMBERsuffI	 I	 IValti	 3	 SiFigure 5: c-structure for (3)N Iktz $ 	 ,e 3 ill	 1A-(4PEED	 ' fts0. 4 10 :pro 1, Is	 .t+, CASE nom, GE-SEtt female, NUM sg, PEES 3, PEON-FORM	 , PEON-TYPE pars, TOPICALIZZOION-FORM' 1"pro'	21DarCASIE$ af cc, PEES12RED 'pro'NTYPE pRAIN pronotuiSPEC FeER 14 rfSS'In3 ;ER-TORM	 NUDGER-TYPE carI'DV-TYPE vp-adv, non -roam 'tie • , PRON-TYPE 'null'DF	 BORICnoudnal [0:protiTVS-ASP 14')OD indicative, 'TENSE paso24 PASSIVE -, STMT-TYPE decl, VTYPE mainFigure 6: f-structure for (3)Our rules do not apply (20) and (21) when parsing (6). Thus, our system outputs only oneanalysis by using (22); this is shown in Fig. 7 and Fig. 8. In other words, `balcarr in (6) isinterpreted as FPP, but not FS, in our system.DBJauNcr20453CS 1:	 ROOT-/NSadj PERIOD	I	 IS,-------"---rl"'"'""-------.NP	 NP	 VverbNadj PPsubj Nadj PPobj V EPcnt FPP AUXVvI	 I	 I	 I	 I	 I	 I	 IPROS	 it	 Nzero	 dit,4 t abN 19 /,'I INfittrIFigure 7: c-structure for (6)igAttc a I-4n1--1- V ft'gb t irbs) ash,,.1RED	 'ft .-<4 4(0:prol, (8,1'4 =1,--i' l .1Ix +, CASE nota, GEND -SEM female, NUM sg, PERS 1, MON-FORM ttt , PROM-TYPE pars, 70PICALISSATION-TORM ' cil'pro'SE acc, PERS 3, f-N ni.,– /. 1TOCCISverbialra3 k, k14.4 n 1-"-- l'. iPICnotainai ( (0 :pro*TNS -ASP low indicative, PROM +, TENSE press14 FOCUS-FORM • ais.h ' , PASSIVE -, STMT-TYPE decl, VTYVE MainFigure 8: f-structure for (6)6 ConclusionIn this paper, we proposed phrase structure rules and lexical entry constraints that successfullytreat Japanese focus particles on the basis of the LFG formalism. The proposed rules andconstraints cover the numerous constructions with focus particles, while properly accounting forambiguities caused by focus particles and not producing redundant analyses. We incorporatedthe proposed rules and constraints into our Japanese LFG system and obtained reasonablec-structures and f-structures for sentences with focus particles.AcknowledgementsWe acknowledge our indebtedness to all the members of the ParGram project, especially RonaldKaplan, Tracy Holloway King and John Maxwell at Palo Alto Research Center, and MaryDalrymple at King s College London, and Livia Polanyi at FX Palo Alto Laboratory, for theircomments and discussions on early versions of the Japanese LFG grammar and system. Wewould also like to thank Tracy Holloway King at PARC for her helpful comments on an earlierdraft of this paper.Dr454ReferencesButt, M., Dyvik H., T.H. King, H. Masuichi, and C. Rohrer. 2002. The parallel grammar project. InCOLING 2002 Workshop on Grammar Engineering and Evaluation, pages 1-7.Butt, M., T.H. King, M.-E. Nino, and F. Segond. 1999. A Grammar Writer's Cookbook. CSLI Publica-tions, Stanford.Dalrymple, M. 2001. Lexical Functional Grammar. Academic Press, New York.IPA. 1987. Lexicon of the japanese language for computers ipal. Technical report, Information-technologyPromotion Agency'(IPA).Kaplan, R.M. and J. Bresnan. 1982. Lexical-Functional Grammar: A formal system for grammaticalrepresentation. The MIT Press, Cambridge, MA.Kim, R., M. Dalrymple, R.M. Kaplan, T.H. King, H. Masuichi, and T. Ohkuma. 2003. Multilingualgrammar development via grammar porting. In 2003 European Summer School in Logic, Language,and Information (ESSLLIO3) workshop "Ideas and Strategies for Multilingual Grammar Development".To appear.Masuichi, H. and T. Ohkuma. 2003. Constructing a practical Japanese parser based on Lexical FunctionalGrammar. Journal of Natural Language Processing (in Japanese), 10(2):79-109.Masuichi, H., T. Ohkuma, H. Yoshimura, and Y. Harada. 2003. Japanese parser on the basis of theLexical-Functional Grammar formalism and its evaluation. In The 17th Pacific Asia Conference onLanguage, Information and Computation. To appear.Matsumoto, Y., A. Kitauchi, T. Yamashita, Y. Hirano, H. Matsuda, K. Takaoka, and M. Asahara. 1999.Japanese morphological analysis system Chasen version 2.0 manual 2nd edition. Technical report,Nara Institute of Science and Technology.Maxwell, J. T, III. and R.M. Kaplan. 1993. The interface between phrasal and functional constraints.Computational Linguistics, 19:571-589.Mizutani, S. 1990. Notes of Japanese grammar. Kohan press (in Japanese), Tokyo.Numata, Y., S. Kinsui, and M. Kudo, 2000. Tence, Negation, Focus, pages 153-216. Iwanami (inJapanese), Tokyo.Ohkuma, T. and H. Masuichi. 2002. Treatment of omitted postpositionals and auxiliary verbs. IPSJSIG Notes (in Japanese), 150:141-148.455

The Treatment of Japanese Focus Particles Based on Lexical-Functional Grammar

DSpace at Waseda University

https://waseda.repo.nii.ac.jp/?action=repository_action_common_download&item_id=28812&item_no=1&attribute_id=101&file_no=1

The Treatment of Japanese Focus Particles Based on Lexical-Functional Grammar

Abstract

Similar works

Full text

Available Versions

Waseda University Repository

DSpace at Waseda University