build up vs modernize

build up and modernize both are verbs.

Word	Noun	Adjective	Verb	Adverb
build up	No	No	Yes	No
modernize	No	No	Yes	No

build up (verb)	modernize (verb)
form or accumulate steadily	make repairs, renovations, revisions or adjustments to
enlarge, develop, or increase by degrees or in stages	become technologically advanced
change the use of and make available or usable
bolster or strengthen
prepare oneself for a military confrontation