Lexical functional grammar (LFG) is a reaction to the direction research in the area of transformational grammar began to take in the 1970s. It mainly focuses on syntax, morphology and semantics but does not include phonology (although ideas from Optimality Theory have recently been popular in LFG research). Unlike Chomskian theories of syntax, which have always involved separate levels of linguistic representation being mapped onto each other via transformations, LFG analysis is based on two mutually constraining structure types:
- the structure of functions (f-structure). See feature structure.
- the structure of syntactic constituents (c-structure).
Many syntactic phenomena are explained by the imperfect correspondence between these two kinds of structure, which must be unified in order to create grammatical sentences. In technical terms, LFG rejects the "projection principle" characterising recent work in transformational grammar, which states that syntactic structures are direct representations of certain kinds of semantic information. Instead, LFG proposes more flexible relationships between syntactic and semantic structure, thereby obviating the need for transformations.
The development of the theory was initiated by Joan Bresnan and Ronald Kaplan in the 70s. A central goal is to create a model of grammar with a depth which appeals to linguists while at the same time being efficiently parseable and having the rigidity of formalism which computational linguists require.
See also
External links
References
Bresnan, Joan (2001). Lexical Functional Syntax. Blackwell.
Falk, Yehuda N. (2001). Lexical-Functional Grammar: An Introduction to Parallal Constraing-Based Syntax. CSLI.
(Introductions to LFG which assume a basic knowledge of syntactic theory.)
