Relational grammar

In linguistics, relational grammar (RG) is a syntactic theory which argues that primitive grammatical relations provide the ideal means to state syntactic rules in universal terms. Relational grammar began as an alternative to transformational grammar.

In relational grammar, constituents that serve as the arguments to predicates are numbered. This numbering system corresponds loosely to the notions of subject, direct object and indirect object. The numbering scheme is subject → (1), direct object → (2) and indirect object → (3). A schematic representation of a clause in this formalism might look like:

One of the components of RG theory is a set of linguistic universals stated in terms of the numbered roles presented above. Such a universal is the Stratal Uniqueness Law which states that there can be "at most one 1, 2, and 3 per stratum.

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