Since qualities of events are reduced to their time, location, character and intensity, the main syntactic function of adverbs is that of an.
Da Vinci had been a cryptology pioneer, Sophie knew, although he was seldom given credit. (Brown) ( of time/frequency)
…she calculated very carefully the intervals between one ink-spot and another… (Spark) ( of degree and of manner)
Miss Brodie’s special girls were taken home to tea and bidden not to tell the others… (Spark) (adverbial modifier of place)
Adverbs with temporal or locative lexical meaning may also be used attributively, e.g. the journey down, a step forward, a then president, though some grammarians regard these words as adjectives derived from adverbs by conversion.
Western linguists make use of several terms to describe the syntactic status of the adverb. The most general term is modifier (sentence-modifier, noun-modifier, adverb-modifier, verb-modifier,).
Here, it cannot but escape our notice that special attention is paid to the status of a modified word. Therefore, one may claim that the syntactic function of the adverb is defined by Western scholars in accordance with a word combination, namely, according to its head (principal word) rather than in accordance to syntactic and semantic peculiarities of the adverb.
As an adverbial modifier, adverbs may take almost any position in the sentence, and in this they are different from the rest of the parts of speech. Discourse markers are particularly mobile. There is only one position in which the adverb may not occur – it cannot separate the predicate and the direct object.