Acceptable

An acceptable sentence is intelligible, although not always flawless, in its particular language. Acceptability does not necessarily entail that the sentence grammatical by the syntactic rules of its language. It only refers to its intelligibility and likelihood of production according to judgments made by native speakers of the language. Acceptability is closely related to grammaticality, which is an independent attribute. For instance, speech errors can produce ungrammatical but acceptable sentences, which may be considered anomalies.

Examples
An acceptable (and grammatical) sentence of English:
 * More Russians have been to China than North Koreans have.

A somewhat acceptable (and ungrammatical) sentence of English:
 * More Russians has to China been than North Koreans has.

An unacceptable (and grammatical) sentence of English:
 * More Russians have been to China than I have.

An unacceptable (and ungrammatical) sentence of English:
 * More to Russians than China to North Koreans have been.