ADVERBS Besides; briefly; by; chance; even; everChance appears to be used as an adverb:
But the order of the words "thou art," indicates that Shakespeare treated chance as a verb. "How may it chance or chances that," as Hamlet, ii. 2. 343, "How chances it they travel?" Compare--
“How chance thou art returned so soon?
So Tr. and Cr. iii. 1. 151; 2 Hen. IV. iv. 4. 20; Rich. III. iv. 2. 103; M. W. of W. v. 5. 231; P. of T. iv. 1. 23. Compare, however, also--
“How chance the roses there do fade so fast?
where "case" is for the Old French "per-case." This use of chance as an apparent adverb is illustrated by
“If case some one of you would fly from us.
Here "perchance" seems used first as an adverb, then as a verb, "it may chance that." So Shakespeare, perhaps, used chance as an adverb, but unconsciously retained the order of words which shows that, strictly speaking, it is to be considered as a verb.
“Perchance his boast of Lucrece' sovereignty
Suggested this proud issue of a king:
Perchance that envy of so rich a thing
Braving compare, disdainfully did sting.