Grammatical in the context of "Generative grammar"

A line is a unit of writing into which a poem or play is divided: literally, a single row of text. The use of a line operates on principles which are distinct from and not necessarily coincident with grammatical structures, such as the sentence or single clauses in sentences. Although the word for a single poetic line is verse, that term now tends to be used to signify poetic form more generally. A line break is the termination of the line of a poem and the beginning of a new line.

The process of arranging words using lines and line breaks is known as lineation, and is one of the defining features of poetry. A distinct numbered group of lines in verse is normally called a stanza. A title, in certain poems, is considered a line.

Linguistic purism or linguistic protectionism is a concept with two common meanings: one with respect to foreign languages and the other with respect to the internal variants of a language (dialects).The first meaning is the historical trend of the users of a language desiring to conserve intact the language's lexical structure of word families, in opposition to foreign influence which are considered 'impure'. The second meaning is the prescriptive practice of determining and recognizing one linguistic variety (dialect) as being purer or of intrinsically higher quality than other related varieties.

The perceived or actual decline identified by the purists may take the form of a change of vocabulary, syncretism of grammatical elements, or loanwords. The unwanted similarity is often with a neighboring language the speakers of which are culturally or politically dominant. The ideal may invoke logic, clarity, or the grammar of classic languages. It is often presented as a conservative measure, as a protection of a language from the encroachment of other languages or of the conservation of the national Volksgeist, but is often innovative in defining a new standard. It is sometimes part of governmental language policy that is enforced in various ways.

An idiom (the quality of it being known as idiomaticness or idiomaticity) is a syntactical, grammatical, or phonological structure peculiar to a language that is actually realized, as opposed to possible but unrealized structures that could have developed to serve the same semantic functions but did not.

The grammar of a language (its morphology, phonology, and syntax) is inherently arbitrary and peculiar to a specific language (or group of related languages). For example, although in English it is idiomatic (accepted as structurally correct) to say "cats are associated with agility", other forms could have developed, such as "cats associate toward agility" or "cats are associated of agility". Unidiomatic constructions sound wrong to fluent speakers, although they are often entirely comprehensible. For example, the title of the classic book English as She Is Spoke is easy to understand (its idiomatic counterpart is English as It Is Spoken), but it deviates from English idiom in the gender of the pronoun and the inflection of the verb. Lexical gaps are another key example of idiom.

In linguistics, evidentiality is, broadly, the indication of the nature of evidence for a given statement; that is, whether evidence exists for the statement and if so, what kind. An evidential (also verificational or validational) is the particular grammatical element (affix, clitic, or particle) that indicates evidentiality. Languages with only a single evidential have had terms such as mediative, médiatif, médiaphorique, and indirective used instead of evidential.

Evidentiality may be direct or indirect: direct evidentials are used to describe information directly perceived by the speaker through vision as well as other sensory experiences while indirect evidentials consist of the other grammatical markers for evidence such as quotatives and inferentials.

A quotative (abbreviated QUOT) is a grammatical device to mark quoted speech. When a quotation is used, the grammatical person and tense of the original utterance is maintained, rather than adjusting it as would be the case with reported speech. It can be equated with "spoken quotation marks."