Grammaticality

In theoretical linguistics, a speaker's judgement on the well-formedness of a linguistic utterance—called a grammaticality judgement—is based on whether the sentence is produced and interpreted in accordance with the rules and constraints of the relevant grammar. If the rules and constraints of the particular language are followed then the sentence is considered to be grammatical. In contrast, an ungrammatical sentence is one that violates the rules of the given language.

Linguists use grammaticality judgements to investigate the syntactic structure of sentences. Generative linguists are largely of the opinion that for native speakers of natural languages, grammaticality is a matter of linguistic intuition, and reflects the innate linguistic competence of speakers. Therefore, generative linguistics attempts to predict grammaticality judgements exhaustively. On the other hand, for linguists who stress the role of social learning, in contrast to innate knowledge of language, such as Hopper 1987 there has been a gradual abandonment of talk about grammaticality in favour of acceptability.

The concept of grammaticality is closely tied to generative grammar, which has the goal of generating all and only the well-formed sentences in a given language.

According to Chomsky, a speaker's grammaticality judgement is based on two factors:

In his study of grammaticality in the 1950s, Chomsky identified three criteria which cannot be used to determine whether or not a sentence is grammatical.

To illustrate this point, Chomsky created the nonsensical sentence in (1), which does not occur in any corpus, is not meaningful, and is not statistically probable. However, the form of this sentence is judged to be grammatical by many native speakers of English. Such grammaticality judgements reflect the fact that the structure of sentence (1) obeys the rules of English grammar. This can be seen by comparing sentence (1) with sentence (2). Both sentences have the same structure, and both are grammatically well-formed.

A grammatical string is not necessarily meaningful, as exemplified by Chomsky’s famous sentence ‘Colorless green ideas sleep furiously’. However, language speakers can still understand nonsensical string by natural intonation and that speakers are able to recall them more easily than ungrammatical sentences. It is also suggested that speakers are supposed to have intuitions about grammaticality, which is determined by their competence on that language.

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