for certain vs sure enough

for certain and sure enough both are adverbs.

Word	Noun	Adjective	Verb	Adverb
for certain	No	No	No	Yes
sure enough	No	No	No	Yes

As adverbs, for certain and sure enough are synonyms defined as:

for certain and sure enough: definitely or positively (`sure' is sometimes used informally for `surely')

Other synonyms of for certain include certainly, for sure, sure, sure as shooting, surely.

for certain (adverb)	sure enough (adverb)
definitely or positively (`sure' is sometimes used informally for `surely')	as supposed or expected
	definitely or positively (`sure' is sometimes used informally for `surely')