Surely happiness is reflective, like the light of heaven. 
     —­IRVING.

     We are offered six months’ credit; and that, perhaps, has
     induced some of us to attend it.—­FRANKLIN.

[Sidenote:  Definition.]

280.  An adverb, then, is a modifying word, which may qualify an action word or a statement, and may add to the meaning of an adjective or adverb, or a word group used as such.

NOTE.—­The expression action word is put instead of verb, because any verbal word may be limited by an adverb, not simply the forms used in predication.

281.  Adverbs may be classified in two ways:  (1) according to the meaning of the words; (2) according to their use in the sentence.

ADVERBS CLASSIFIED ACCORDING TO MEANING.

282.  Thus considered, there are six classes:—­

(1) Time; as now, to-day, ever, lately, before, hitherto, etc.

(2) Place.  These may be adverbs either of

(a) PLACE WHERE; as here, there, where, near, yonder, above, etc.

(b) PLACE TO WHICH; as hither, thither, whither, whithersoever, etc.

(c) PLACE FROM WHICH; as hence, thence, whence, whencesoever, etc.

(3) Manner, telling how anything is done; as well, slowly, better, bravely, beautifully.  Action is conceived or performed in so many ways, that these adverbs form a very large class.

(4) Number, telling how many times:  once, twice, singly, two by two, etc.

(5) Degree, telling how much; as little, slightly, too, partly, enough, greatly, much, very, just, etc. (see also Sec. 283).

(6) Assertion, telling the speaker’s belief or disbelief in a statement, or how far he believes it to be true; as perhaps, maybe, surely, possibly, probably, not, etc.

[Sidenote:  Special remarks on adverbs of degree.]

283.  The is an adverb of degree when it limits an adjective or an adverb, especially the comparative of these words; thus,—­

     But not the less the blare of the tumultuous organ wrought its
     own separate creations.—­DE QUINCEY.

     The more they multiply, the more friends you will have; the
     more evidently they love liberty, the more perfect will be
     their obedience.—­BURKE.

This and that are very common as adverbs in spoken English, and not infrequently are found in literary English; for example,—­