LECTURE 6 Introduction to LFG 2. The f structure CONTENTS 1. F structure building blocks...1 3.1. Grammatical Functions (GFs)...1 3.2. Semantic forms...2 3.3. Other features...3 2. LFG s axioms...3 3. References...5 1. F structure building blocks F structures are feature structures that have specified features (attributes) and some of them, have special forms of values. Reentrancies also occur, normally representing linguistic constraints. In LFG, f structures are used to represent the syntactic functions of constituents. LFG claims that a separate level or representation dedicated to syntactic functions helps to better represent a set of important linguistic phenomena. 3.1. Grammatical Functions (GFs) GF Governable Syntactic functions of GFs SUBJ(ect) yes Subject verb agreement, control phenomena (1) OBJ(ect) yes In contrast with the SUBJ, passive voice (2) OBJ(ect)2 yes Special semantic contribution, passive voice in English (3) OBL(ique) θ yes Clear semantic contribution required by a predicate (4) ADJ(unct) no Uncontrolled adjunct, in contrast with the logical arguments of the predicate it is related to (5) COMP(lement) yes Clausal complement whose subject is not controlled by the SUBJ or the OBJ of the mother predicate (6) XCOMP(lement) yes Clausal complement whose subject is controlled by the SUBJ or the OBJ of the mother predicate (7) XADJ(unct) no Controlled adjunct, in contrast with the logical arguments of the predicate it is related to (8) Table 1. Grammatical Functions in LFG Syntax is not a matter of arrangement of constituents only. Constituents stand in functional relations. This is an ancient idea which LFG exploits. LFG recognizes the grammatical 1
functions in Table 1. In LFG, GFs are considered primitives of linguistic theory. Furthermore, GFs are distinguished into governable and non governable ones; governable GFs are required by a head predicate and have an important impact on phrasal well formedness. Non governable GFs are not required by a head predicate. (1) Agreement: Τα παιδιά τρώνε κολατσιό *Το παιδί τρώνε κολατσιό Subject control: Ανεβάζοντας τη φωνή της, η Μαρία είπε: * Ανεβάζοντας τη φωνή του, η Μαρία είπε: Agent theme pairs: Τρώω μακαρόνια. Γράφω γράμμα. (2) Passives: Ο Γιώργος γράφει ένα κείμενο. Το κείμενο γράφτηκε από τον Γιώργο. Agent theme pairs: Τρώω μακαρόνια. Γράφω γράμμα. (3) Dative shift: John gave Mary a kiss. Mary was given a kiss by John. (dialectic) A kiss was given Mary by John. (4) Semantic restriction: Έδωσε ένα φιλί στην Μαρία. *Έδωσε ένα φιλί από/για/με την Μαρία (meaning that Maria was the receiver). (5) Έφυγε με το ποδήλατο χθές. Έφυγε. (6) Υποθέτω ότι θα έρθεις. Τί υποθέτω? Επιμένω να έρθεις. *Τι επιμένω? (7) Subject control: Μπορώ να έρθω *Μπορώ να έρθεις (8) Subject control: Ανεβάζοντας τη φωνή της, η Μαρία είπε: * Ανεβάζοντας τη φωνή του, η Μαρία είπε: In an f structure, governable GFs are features that take other f structures as values. Nongovernable GFs are features take sets of f structures as values. 3.2. Semantic forms This is how predicate requirements on syntax are listed in the lexicon: PREDICATE (^GF1, ^GF2,...) Functional Equation where GFi a governable GF παιδί τρέχω ((^SUBJ) αγαπώ (^SUBJ, ^OBJ) θέλω (^SUBJ, ^COMP) μπορώ (^SUBJ, ^XCOMP) 2
^XCOMP SUBJ = ^ SUBJ persuade (^SUBJ, ^OBJ, ^XCOMP) ^XCOMP SUBJ = ^ OBJ In an f structure a semantic form turns up as the value of the feature PRED. Actually, this is a distinguished attribute value pair since no other feature can have a semantic form as its value. Most importantly, only one semantic form can exist in an f structure. Functional equations turn up as reentrancies in the f structure. 3.3. Other features Features such as TENSE, MOOD, CASE etc also turn up in an f structure. LFGW: http://arts.anu.edu.au/linguistics/software/lfgw.html parsing: [Mary,washed,the,small,smelly,happy,horse,.] structure # 1 PRED Wash<SUBJ,OBJ> S TENSE PAST / \ MOOD FIN NP VP SUBJ PRED Mary / \ CASE NOM Pn V NP OBJ PRED Horse / / \ \ MOD [PRED Happy], Mary washed Det AP AP AP N [PRED Smelly], [PRED Small] the A A A horse SPEC DEF CASE ACC small smelly happy 1 structure found Note: For reasons of presentation, the output of LFGW has been edited a bit only as regards the graphics. 2. LFG s axioms Lexical integrity: No syntactic rules can refer to elements of morphological structure. Λεξική ακεραιότητα. Κανένας συντακτικός κανόνας δεν μπορεί να αναφερθεί σε στοιχεία της μορφολογικής δομής So, the lexicon, where words are formed, is separate from syntax. Coherence: In a given f structure a particular attribute may have at most one value. 3
Μοναδικότητα. Σε μια λειτουργική δομή κάθε χαρακτηριστικό έχει μία και μόνο μία τιμή. This is actually the definition of the mathematical notion function. Notice that ADJ receives a set as a value, that is, there may be many adjuncts in a phrase but they are all members of the same set. Completeness: An f structure is locally complete if and only if it contains all the governable grammatical functions that its predicate governs. An f structure is complete if and only if it and its subsidiary f structures are locally complete. Πληρότητα. Μια λειτουργική δομή είναι τοπικά πλήρης εάν και μόνον εάν περιέχει όλες τις κυβερνούμενες γραμματικές συναρτήσεις τις οποίες κυβερνά το κατηγόρημά της. Μία λειτουργική δομή είναι πλήρης εάν και μόνον εάν όλες οι επιμέρους λειτουργικές δομές είναι τοπικά πλήρεις....ok, this is to do away with say *he devoured, *περπάτησε στο. Coherence: An f structure is locally coherent if and only if all the governable grammatical functions that it contains are governed by a local predicate. An f structure is coherent if and only if it and all its subsidiary f structures are locally coherent. Συνεκτικότητα. Μία λειτουργική δομή είναι τοπικά συνεκτική εάν και μόνον εάν όλες οι κυβερνώμενες γραμματικές συναρτήσεις τις οποίες περιέχει κυβερνώνται από ένα τοπικό κατηγόρημα. Μία λειτουργική δομή είναι συνεκτική εάν και μόνον εάν όλες οι επιμέρους λειτουργικές δομές είναι τοπικά συνεκτικές. This is to do away with *John Mary love children flowers. Exercise 1. Consider the Greek sentence Το κορίτσι άνοιξε την πόρτα. Give the lexical entries, the PS rules and c and the f structure. Exercise 2. Consider the following structures. Ο Γιώργος αγόρασε από τον Γιάννη μια μηχανή για 1000 Ευρώ. Αγόρασε από τον Γιάννη μια μηχανή για 1000 Ευρώ. Ο Γιώργος αγόρασε από τον Γιάννη μια μηχανή. Αγόρασε από τον Γιάννη μια μηχανή. Ο Γιώργος αγόρασε μια μηχανή. Αγόρασε μια μηχανή. Discuss these facts in the light of the axiom of completeness. What does this imply for the theory of linguistics and for the implemented grammar? Exercise 3. Consider clitic doubling. Tο είδα το παιδί. Toυ το είπα του Γιάννη το νέο. Which LFG axiom do they seem to violate? Why? How could such a situation be treated? Exercise 5. LFGW: http://arts.anu.edu.au/linguistics/software/lfgw.html Tutorial 2. Develop on LFGW0.9 a Greek toy grammar that fully parses the sentences below (with 4
functional annotations, that is) and discuss the results. In particular, what are the benefits from the architectural choices of LFG? το παιδί παίζει παίζει το παιδί τα παιδιά τρώνε τρώνε τα παιδιά το παιδί τρώει τη τυρόπιττα τρώει το παιδί τη τ υρόπιττα τα παιδιά τρώνε τα μήλα τρώνε τα παιδιά τα μήλα 3. References Dalrymple, Mary. 2002. Syntax and Semantics 34: Lexical Functional Grammar. Academic Press 5