Introduction to Lexical Functional Grammar Mary Dalrymple, John Lowe, & Louise Mycock Centre for Linguistics and Philology Oxford University Konstanz, November/December 2012
• “Semantic roles, syntactic constituents, and grammatical functions belong to parallel information structures of very different formal character. They are related not by proof-theoretic derivation but by structural correspondences, as a melody is related to the words of a song. The song is decomposable into parallel melodic and linguistic structures, which jointly constrain the nature of the whole. In the same way, the sentences of human language are themselves decomposable into parallel systems of constraints – structural, functional, semantic, and prosodic – which the whole must jointly satisfy.” (Bresnan, 1990)
LFG Two aspects of syntactic structure: • Functional structure is the abstract functional syntactic organisation of the sentence, familiar from traditional grammatical descriptions, representing syntactic predicate-argument structure and functional relations like subject and object. • Constituent structure is the overt, more concrete level of linear and hierarchical organisation of words into phrases.
LFG’s c-structure and f-structure IP I ′ NP ‘ GREET � SUBJ , OBJ � ’ PRED N VP � � ‘D AVID ’ SUBJ PRED David V ′ � � ‘C HRIS ’ OBJ PRED V NP greeted N Chris
Functional structure ‘ GO � SUBJ � ’ PRED TENSE PAST � � ‘D AVID ’ PRED SUBJ NUM SG • PRED , TENSE NUM : attributes • ‘ GO � SUBJ � ’ , D AVID , SG : values • PAST , SG : symbols (a kind of value) • ‘ BOY ’ , ‘ GO � SUBJ � ’ : semantic forms
F-structures ‘ GO � SUBJ � ’ PRED TENSE PAST � � ‘D AVID ’ PRED SUBJ NUM SG �� �� ‘ QUICKLY ’ ADJ PRED An f-structure can be the value of an attribute. Attributes with f-structure values are the grammatical functions: SUBJ , OBJ , OBJ θ , COMP , XCOMP , ...
F-structures ‘ GO � SUBJ � ’ PRED TENSE PAST � � ‘D AVID ’ PRED SUBJ NUM SG �� �� ‘ QUICKLY ’ ADJ PRED A set of f-structures can also be a value of an attribute.
Sets of f-structures ‘ GO � SUBJ � ’ PRED TENSE PAST � � ‘D AVID ’ PRED SUBJ � � ‘G EORGE ’ PRED �� �� ‘ QUICKLY ’ ADJ PRED Sets of f-structures represent: • adjuncts (there can be more than one adjunct) or • coordinate structures (there can be more than one conjunct)
C- and F-Structure � � φ V ‘ GREET � SUBJ , OBJ � ’ PRED TENSE PAST greeted φ function relates c-structure nodes to f-structures. (Function: Every c-structure node corresponds to exactly one f-structure.)
Constraining the c-structure/f-structure correspondence φ V ′ � � ‘ YAWN � SUBJ � ’ PRED V TENSE PAST yawned − → V V ′
Local F-Structure Reference φ V ′ � � ‘ YAWN � SUBJ � ’ PRED V TENSE PAST yawned − → V V ′ the current c-structure node (“self”): ∗ the immediately dominating node (“mother”): � ∗ the c-structure to f-structure function: φ
Rule Annotation φ V ′ � � ‘ YAWN � SUBJ � ’ PRED V TENSE PAST yawned − → V ′ V φ ( � ∗ ) = φ ( ∗ ) mother’s ( V ′ ’s) f-structure = self’s ( V’s ) f-structure
Simplifying the Notation φ ( � ∗ ) (mother’s f-structure) = ↑ φ ( ∗ ) = ↓ (self’s f-structure) φ V ′ � � ‘ YAWN � SUBJ � ’ PRED V TENSE PAST yawned − → V ′ V ↑ = ↓ mother’s f-structure = self’s f-structure
Using the Notation − → V ′ V ↑ = ↓ mother’s f-structure = self’s f-structure V ′ V ↑ = ↓
Using the Notation − → V ′ V ↑ = ↓ mother’s f-structure = self’s f-structure V ′ V ↑ = ↓
Using the Notation − → V ′ V ↑ = ↓ mother’s f-structure = self’s f-structure V ′ V ↑ = ↓
Using the Notation − → V ′ V ↑ = ↓ mother’s f-structure = self’s f-structure [ ] V ′ V ↑ = ↓
More rules − → V ′ V NP φ ( � ∗ ) = φ ( ∗ ) ( φ ( � ∗ ) OBJ ) = φ ( ∗ ) mother’s f-structure’s OBJ = self’s f-structure In simpler form: − → V ′ V NP ↑ = ↓ ( ↑ OBJ ) = ↓
Using the Notation − → V ′ V NP ↑ = ↓ ( ↑ OBJ ) = ↓ � � [ ] OBJ V ′ V NP
Terminal nodes � � V ‘ YAWN � SUBJ � ’ PRED TENSE PAST yawned Expressible as: yawned − → V ( ↑ PRED ) = ‘ YAWN � SUBJ � ’ ( ↑ TENSE ) = PAST Standard form: yawned ( ↑ PRED ) = ‘ YAWN � SUBJ � ’ V ( ↑ TENSE ) = PAST
Phrase structure rules: English � � � � I ′ NP − → IP ( ↑ SUBJ ) = ↓ ↑ = ↓ � � � � I VP − → I ′ ↑ = ↓ ↑ = ↓ � � V VP − → ↑ = ↓ � � N NP − → ↑ = ↓
Lexical entries: English yawned ( ↑ PRED ) = ‘ YAWN � SUBJ � ’ V ( ↑ TENSE ) = PAST David ( ↑ PRED ) = ‘D AVID ’ N (Standard LFG practice: include only features relevant for analysis under discussion.)
Analysis: English IP NP I ′ ( ↑ SUBJ ) = ↓ ↑ = ↓ N VP ↑ = ↓ ↑ = ↓ David V ↑ = ↓ ( ↑ PRED ) = ‘D AVID ’ yawned ( ↑ PRED ) = ‘ YAWN � SUBJ � ’ ( ↑ TENSE ) = PAST
Analysis: English IP NP I ′ ( ↑ SUBJ ) = ↓ ↑ = ↓ N VP ↑ = ↓ ↑ = ↓ David V ↑ = ↓ ( f n PRED ) = ‘D AVID ’ yawned ( ↑ PRED ) = ‘ YAWN � SUBJ � ’ ( ↑ TENSE ) = PAST
Analysis: English IP NP I ′ ( ↑ SUBJ ) = ↓ ↑ = ↓ N VP f np = f n ↑ = ↓ David V ↑ = ↓ ( f n PRED ) = ‘D AVID ’ yawned ( ↑ PRED ) = ‘ YAWN � SUBJ � ’ ( ↑ TENSE ) = PAST
Analysis: English IP NP I ′ ( f ip SUBJ ) = f np ↑ = ↓ N VP f np = f n ↑ = ↓ David V ↑ = ↓ ( f n PRED ) = ‘D AVID ’ yawned ( ↑ PRED ) = ‘ YAWN � SUBJ � ’ ( ↑ TENSE ) = PAST
Analysis: English IP NP I ′ ( f ip SUBJ ) = f np ↑ = ↓ N VP f np = f n ↑ = ↓ David V ↑ = ↓ ( f n PRED ) = ‘D AVID ’ yawned ( f v PRED ) = ‘ YAWN � SUBJ � ’ ( f v TENSE ) = PAST
Analysis: English IP NP I ′ ( f ip SUBJ ) = f np ↑ = ↓ N VP f np = f n ↑ = ↓ David V f vp = f v ( f n PRED ) = ‘D AVID ’ yawned ( f v PRED ) = ‘ YAWN � SUBJ � ’ ( f v TENSE ) = PAST
Analysis: English IP NP I ′ ( f ip SUBJ ) = f np ↑ = ↓ N VP f i ′ = f vp f np = f n David V f vp = f v ( f n PRED ) = ‘D AVID ’ yawned ( f v PRED ) = ‘ YAWN � SUBJ � ’ ( f v TENSE ) = PAST
Analysis: English IP NP I ′ ( f ip SUBJ ) = f np f ip = f i ′ N VP f i ′ = f vp f np = f n David V f vp = f v ( f n PRED ) = ‘D AVID ’ yawned ( f v PRED ) = ‘ YAWN � SUBJ � ’ ( f v TENSE ) = PAST
Solving the Description ( f ip SUBJ ) = f np ‘ YAWN � SUBJ � ’ PRED f ip f np = f n TENSE PAST f i ′ ( f n PRED ) = ‘D AVID ’ � � f vp f np ‘D AVID ’ f ip = f i ′ SUBJ PRED f v f n f i ′ = f vp f vp = f v ( f v PRED ) = ‘ YAWN � SUBJ � ’ ( f v TENSE ) = PAST
Final result ‘ YAWN � SUBJ � ’ PRED TENSE PAST � � IP ‘D AVID ’ SUBJ PRED NP I ′ ( f ip SUBJ ) = f np f ip = f i ′ N VP f i ′ = f vp f np = f n David V ( f n PRED ) = ‘D AVID ’ f vp = f v yawned ( f v PRED ) = ‘ YAWN � SUBJ � ’ ( f v TENSE ) = PAST
Semantics in LFG IP I ′ NP N ′ VP ‘ MARRY � SUBJ , OBJ � ’ PRED � � V ′ N ‘J OHN ’ SUBJ PRED � � John V NP ‘R OSA ’ OBJ PRED married N ′ N Rosa Meaning: marry ( john , rosa ) How is this meaning composed?
Glue: Composing meanings via deduction Glue (Asudeh, 2004, 2012; Dalrymple, 1999, 2001): Meaning assembly and linear logic • Logic of meanings (semantic level): the level of meanings of utterances and phrases • Logic for composing meanings (‘glue’ level): the level responsible for assembling the meanings of parts to get the meaning of the whole
Meanings Meanings are expressions like David , yawn(David) , yawn ... Function: when applied to an argument, yields a unique value. yawn : applied to David , yields “true”. applied to Fred , yields “true”. applied to George , yields “false”. ... Function application: yawn applied to David = yawn(David)
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