It posits two separate levels of syntactic structure, a phrase structure grammar representation of word order and constituency, and a representation of grammatical functions such as subject and object, similar to dependency grammar.
The f-structure analysis, on the other hand, treats the sentence as being composed of attributes, which include features such as number and tense or functional units such as subject, predicate, or object.
Another feature of LFG is that grammatical-function changing operations like passivization are relations between word forms rather than sentences.
Active and passive verbs involve alternative mapping of the participants to grammatical functions.
Because of this, computational parsers have been developed and LFG has also been used as the theoretical basis of various machine translation tools, such as AppTek's TranSphere, and the Julietta Research Group's Lekta.