Lexical Functional Grammar : Grammar Formalisms Spring Term 2004
Lions seem to live in the forest DET N P NP V PP COMP VP N V VP-bar NP VP S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘seem SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM INF PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF +
Lions seem to live in the forest DET N P NP V PP COMP VP N V VP-bar NP VP S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘seem SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM INF PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF + f1 f3 f2 f4 f5 f6 n7 n6 n5 n4 n3 n2 n1 n10 n9 n8 n11 n13 n12 n14
Lions seem to live in the forest DET N P NP V PP COMP VP N V VP-bar NP VP S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘seem SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM INF PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF + f1 f3 f2 f4 f5 f6 n7 n6 n5 n4 n3 n2 n1 n10 n9 n8 n11 n13 n12 n14
Properties of the mapping from c- structure to f-structure Each c-structure node maps onto at most one f-structure node. More than one c-structure node can map onto the same f-structure node. An f-structure node does not have to correspond to any c-structure node. (But the information it contains does come from somewhere – either a grammar rule or lexical entry.)
Φ is a mapping from c-structure nodes to f- structure nodes. –There are other mappings to semantic structures, argument structures, discourse structures,etc. * is the “current” c-structure node (me). Φ(*) is “my f-structure” ( ) m(*) is “my c-structure mother” Φ(m(*)) is “my c-structure mother’s f-structure” ( ) The formalism for grammatical encoding : Local co-description of partial structures
Local co-description of partial structures S NP VP ( SUBJ) = = NP says: My mother’s f-structure has a SUBJ feature whose value is my f-structure. VP says: My mother’s f-structure is my f-structure. This rule simultaneously describes a piece of c- structure and a piece of f-structure. It is local because each equation refers only to the current node and its mother. (page )
Other types of equations F-structure composition –( SUBJ NUM) = sg –My f-structure has a subj feature, whose value is another f-structure, which has a num feature, whose value is sg. –Usually, path names are not longer than two. Two features pointing to the same value: –( SUBJ) = ( XCOMP SUBJ) –( SUBJ) = ( TOPIC) ( ( CASE)) = (Dalrymple pages ) –Sam walked in the park. –( CASE) = OBL-loc –( OBL-loc) =
The minimal solution The f-structure for a sentence is the minimal f-structure that satisfies all of the equations. (page 101).
Building an F-structure: informal, for linguists Annotate –Assign a variable name to the f-structure corresponding to each c-structure node. –May find out later that some of them are the same. Instantiate –Replace the arrows with the variable names. Solve –Locate the f-structure named on the left side of the equation. –Locate the f-structure named on the right side of the equation –Unify them. –Replace both of them with the result of unification.
Lions seem to live in the forest DET N P NP V PP COMP VP N V VP-bar NP f2 VP f3 S f1 SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘seem SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM INF PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF + Rule: S → NP VP (↑ SUBJ) = ↓ ↑=↓ (↑VFORM) = fin Instantiated equations: (f1 SUBJ) = f2 f1 = f3 f1 f2 f3
Equivalent to drawing f-structures on nodes as in TAG S [1] [ VFORM fin ] NP VP [1] [ SUBJ [2] ] [1]
Lions seem to live in the forest DET N P NP V PP COMP VP f4 N f5 V VP-bar NP VP S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘seem SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM INF PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF + lion: N seem: V (↑ PRED) = `lion’ (↑ PRED) = ‘seem SUBJ’ XCOMP (↑ SUBJ) = (↑ XCOMP SUBJ) -s (suffix for nouns) (↑ NUM) = pl - Ø (suffix for verbs) (↑ PERS) = 3 (↑ VFORM) = fin (↑ SUBJ NUM) = pl f5 f4
Lions seem to live in the forest DET N P NP V PP COMP VP f4 N f5 V VP-bar NP VP S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘seem SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM INF PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF + lion: N seem: V (f4 PRED) = `lion’ (f5 PRED) = ‘seem SUBJ’ XCOMP (f5 SUBJ) = (f5 XCOMP SUBJ) -s (suffix for nouns) (f4 NUM) = pl - Ø (suffix for verbs) (f4 PERS) = 3 (f5 VFORM) = fin (f5 SUBJ NUM) = pl f5 f4
What is an XCOMP A non-finite clause, predicate nominal, predicate adjective, or predicate PP –Sam seemed to be happy (VP) –Sam seemed happy (AP) –Sam became a teacher (NP) –We had them arrested (VP) –We kept them in the drawer (PP) Has to be an argument of a verb: –Arrested by the police, Sam had no alternative but to give up his life of crime. This is an adjunct, not an XCOMP Gets its subject by sharing with another verb: –I think that Sam is happy. This is a COMP, not an XCOMP
Lions seem to live in the forest DET N P NP f7V PP f6COMP VP f9 N f5 V f8 VP-bar NP VP f3 S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘seem SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM INF PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF + seem: V (↑ PRED) = ‘seem SUBJ’ XCOMP ( ↑ SUBJ) = ( ↑ XCOMP SUBJ) ( ↑ XCOMP VFORM) = INF - Ø (suffix for verbs) ( ↑ VFORM) = fin ( ↑ SUBJ NUM) = pl to: COMP - Ø (suffix for verbs) ( ↑ VFORM) = INF live: V ( ↑ PRED) = `live ’ SUBJ OBL VP → V VP ↑=↓ (↑ XCOMP) = ↓ f3 f5 f9 f8 f7 f6
Lions seem to live in the forest DET N P NP f7V PP f6COMP VP f9 N f5 V f8 VP-bar NP VP f3 S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘seem SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM INF PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF + seem: V (f5 PRED) = ‘seem SUBJ’ XCOMP (f5 SUBJ) = (f5 XCOMP SUBJ) (f5 XCOMP VFORM) = INF - Ø (suffix for verbs) (f5 VFORM) = fin (f5 SUBJ NUM) = pl to: COMP - Ø (suffix for verbs) (f6 VFORM) = INF (f7 VFORM) = INF live: V (f7 PRED) = `live ’ SUBJ OBL VP → V VP f3=f5 (f3 XCOMP) = f8 f3 f5 f9 f8 f7 f6
Lions try to live in the forest DET N P NP V PP COMP VP N V VP-bar NP VP S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘try ’ SUBJ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM INF PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF +
Lions have lived in the forest DET N P NP V PP VP N V NP VP S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘have SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM PASTPART PRED ‘live ’ SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF + have: V (↑ PRED) = ‘have SUBJ’ XCOMP ( ↑ SUBJ) = ( ↑ XCOMP SUBJ) ( ↑ XCOMP VFORM) = PASTPART - Ø (suffix for verbs) ( ↑ VFORM) = fin ( ↑ SUBJ NUM) = pl
Lions were hunted in the forest DET N P NP V PP VP N V NP VP S SUBJ PRED ‘lion’ NUM pl PERS 3 PRED ‘be SUBJ’ XCOMP TENSE pres VFORM fin XCOMP SUBJ [ ] VFORM PASSIVE PRED ‘hunt ’ Ø SUBJ OBL-loc OBJ OBL -loc CASE OBL-loc PRED ‘in ’ OBJ PRED ‘forest’ NUM sg PERS 3 DEF + were : V (↑ PRED) = ‘be SUBJ’ XCOMP ( ↑ SUBJ) = ( ↑ XCOMP SUBJ) ( ↑ XCOMP VFORM) = PASSIVE ( ↑ VFORM) = fin ( ↑ SUBJ NUM) = pl