ABSTRACT

The criterion developed by N.Chomsky for evaluating grammatical descriptions of natural languages. There are three distinct levels: observational adequacy, descriptive adequacy, and explanatory adequacy. Observational adequacy describes those grammars which present the primary linguistic data correctly and completely. A grammar is descriptively adequate if it accounts for the intuitions and competence ( competence vs performance) of the speaker regarding the regularity and rules of the language. The comprehensive requirements for explanatory adequacy are met if the grammatical description is handled in accord with a linguistic theory which specifies linguistic universals ( universal grammar) and also supports a theory of language acquisition. Such a theory provides the basis on which the most adequate explanatory grammar can be chosen from several descriptively adequate grammars.