Adverbs may be classified not only on the ground of their morphemic composition but also on the ground of their semantic characteristics. As a rule, semantically, adverbs are divided into the two large classes: 1) qualita­tive, 2) quantitative and 3) circumstantial.

Qualitative adverbs express immediate, inherently non-graded quali­ties of actions and other qualities. In the majority of cases they have a formal property: they are derived from adjectives by means of the suffix -ly, with the exception of the so-called flat adverbs well, fast, low, hard whose form coincides with that of adjectives. One should also bear in mind that the flat adjectives have a parallel form in -ly with an obvious difference in mean­ing or connotation. Cf. to work hard – hardly to work, to fall flat onto the floor – to refuse flatly, to fly high over the city – to discuss a highly philo­sophical problem, etc.

Qualitative adverbs perform the function of an adverbial modifier of manner (gladly, happily, steadily, increasingly). 

Quantitative adverbs include words of degree. These are specific lexi­cal units of semi-functional nature expressing measure, or gradational eval­uation of qualities. They undergo a further subdivision into three clearly distinct groups.

The first group is formed by adverbs of high degree – so-called “intensi-fiers” (very, highly, perfectly, absolutely, strongly, much). Here also belong adverbs of excessive degree (direct and reverse) (too, awfully, tremendously, dreadfully, terrifically) and adverbs of unexpected degree (surprisingly, as­tonishingly, amazingly).

The second group is formed by adverbs of moderate degree (fairly, comparatively, relatively, moderately, rather), approximate degree (almost, nearly) and optimal degree (enough, sufficiently, adequately).

The third group contains adverbs of low degree (slightly, a little, a bit) and inadequate degree (insufficiently, intolerably, unbearably, ridiculously).

As we may see, the degree adverbs constitute a specific variety of quan­titative words. Moreover, they may be called qualitative-quantitative words, since they are used as qualitative evaluators. In this function they are dis­tinctly different from genuine quantitative adverbs which are directly re­lated to numerals and thereby form groups of words of pronominal order, e.g. twice, thrice, twofold, threefold, manifold, etc.

Circumstantial adverbs are divided into notional and functional. The functional circumstantial adverbs are words of pronominal nature that in­clude adverbs of time, place, manner, cause, and consequence. Many of these words are used as syntactic connectives and question-forming func­tion words, e.g. now, here, when, where, so, thus, how, why, etc.

As for circumstantial adverbs of more self-dependent nature, they in­clude three basic groups: 1) adverbs of place (here, near, far, upstairs, for­ward), 2) adverbs of time (now, today, tomorrow, lately), 3) adverbs of fre­quency (always, seldom, often, never). The first two varieties express a gen­eral idea of temporal and spatial orientation and essentially perform deictic functions.

Qualitative and circumstantial adverbs specify different actions and ex­hibit semantically different links with the sentence. Some scholars believe that circumstantial adverbs do not have any specific link with any sentence part but modify the sentence as a whole.