From a far away perspective, FRMG is essentially a large coverage hand-crafted grammar for French that may be used to parse sentences and produces syntactic structures.

Hand-crafting large grammars (or Grammar Engineering) was the way to develop parsers 20 years ago for several important grammatical formalisms such as Tree Adjoining Grammars (TAG), LFGs, HPSGs, CCGs, ...

The arising of successful data-driven approaches have since then largely supplanted hand-crafted grammars and grammar engineering.

Several reproaches have been advanced against hand-crafted grammars:

  • they require a strong expertise both on the linguistic side and about the grammatical formalism. The data-driven approaches allow a separation between people with linguistic expertise to annotate treebanks and people skilled in machine-learning.
  • it is difficult to increase the coverage of the grammar, because of the large diversity of syntactic phenomena to cover but also because of the increasing complexity of the interactions between the different structures of the grammar
  • it becomes also more and more difficult to maintain the grammar over time, modify it and extend it

It is now time to look more closely at FRMG.

FRMG stands for FRench MetaGrammar and is primarily a wide coverage grammatical description for French.

Metagrammars could theoretically be directed used to parse sentences. However, they are mostly designed to ease the work of syntacticians to describe grammatical phenomena using elementary constraints and a modular organization. In practice, metagrammars are used to derive an operational grammar. For FRMG, it is a Tree Adjoining Grammar (TAG).

The grammar is then compiled into a chart-like parser and may then be used to parse.