The systematic ways in which sentences of a language may be built. Grammar is typically studied independently of phonetics and semantics . Its two branches are syntax, or the way words make sentences, and morphology, which includes the recognition of syntactically significant parts of words. A grammar that aspires to find categories and rules applicable to all (human) languages is a universal grammar. Grammar may be pursued in various ways: a formal grammar aspires to the production of a proof procedure or algorithm separating the well-formed sentences of a language from other strings of words. The different levels of complexity of such algorithms defines the hierarchy of abstract structures for languages described originally by Chomsky . A descriptive grammar describes actual usages in a language, whereas a prescriptive grammar legislates for correct and incorrect usage. See also generative grammar.
Philosophy dictionary. Academic. 2011.