1. Definition and function

The adverb is a part of speech which expresses some circumstances that attend an action or state, or points out some characteristic features of an action or a quality [Каушанская, 2006, с. 204].

The adverb expresses either the degree of a property, or the property of an action, or the circumstances under which an action takes place [Ilyish, 1965, p. 152].

Adverbs are char­acterized by a combinability with verbs, adjectives and words of ad­verbial nature. The functions of adverbs in these combinations consist in expressing different adverbial modifiers.

2. Classification of adverbs

According to their structure adverbs are divided into [Каушанская, 2006, с. 204-205; Кобрина, 1999, с. 192-193 и др.]:

- simple: here, there, now, then, so, quite, why, how, where, when, etc.;

• derivative: slowly, likewise, etc.;

• compound: anyhow, sometimes, nowhere;

• composite: at once, at last.

According to their meaning adverbs fall under several groups:

• adverbs of time: today, tomorrow, soon;

• adverbs of repetition or frequency: often, seldom, ever, never, sometimes;

• adverbs of place and direction: inside, outside, here, there;

• adverbs of cause and consequences: accordingly, consequently;

• adverbs of manner: kindly, quickly, hard;

• adverbs of degree, measure and quantity: very, enough, too, almost, much, little, once, twice.

Interrogative adverbs are used in special questions: where, when, why, how. Conjunctive and relative adverbs are used to introduce subordinate clauses.

Adverbs are commonly divided into qualitative, quantitative and circumstantial [Blokh, 2000, p. 105-106].

By qualitative such adverbs are meant as express immediate, in­herently non-graded qualities of actions and other qualities. The typi­cal adverbs of this kind are qualitative adverbs in -ly.

E.g.: The little boy was crying bitterly over his broken toy.

The adverbs interpreted as "quantitative" include words of de­gree. These are specific lexical units of semi-functional nature ex­pressing quality measure, or gradational evaluation of qualities. They may be subdivided into several very clearly pronounced sets:

• adverbs of high degree – "intensifiers": very, quite, entirely, utterly, highly, greatly, perfectly, absolutely, strongly, considerably, pretty, much;

• adverbs of excessive degree (direct and reverse) also belonging to the broader subclass of intensifiers: too, awfully, tremendously, dreadfully, terrifically.

• adverbs of unexpected degree: surprisingly, astonishingly, amazingly.

• adverbs of moderate degree: fairly, comparatively, relatively, moderately, rather.

• adverbs of low degree: slightly, a little, a bit.

• adverbs of approximate degree: almost, nearly.

• adverbs of optimal degree: enough, sufficiently, adequately.

• adverbs of inadequate de­gree: insufficiently, intolerably, unbearably, ridiculously.

• adverbs of under-degree: hardly, scarcely.

Circumstantial adverbs are also divided into notional and func­tional.

The functional circumstantial adverbs are words of pronominal nature. They include adverbs of time, place, manner, cause, consequence: now, here, when, where, so, thus, how, why, etc.

As for circumstantial adverbs of more self-dependent nature, they include two basic sets: first, adverbs of time; second, adverbs of place: today, tomorrow, already, ever, never, shortly, recently, sel­dom, early, late; homeward, eastward, near, far, outside, ashore, etc. The two varieties express a general idea of temporal and spatial orientation and essentially perform deictic (indicative) functions in the broader sense. Bearing this in mind, we may unite them under the general heading of "orientative" adverbs, reserving the term "cir­cumstantial" to syntactic analysis of utterances.