replace vs modify

replace and modify both are verbs.

Word	Noun	Adjective	Verb	Adverb
replace	No	No	Yes	No
modify	No	No	Yes	No

As verbs, modify is a hypernym of replace; that is, modify is a word with a broader meaning than replace:

Other hypernyms of replace include alter, change.

replace (verb)	modify (verb)
substitute a person or thing for (another that is broken or inefficient or lost or no longer working or yielding what is expected)	make less severe or harsh or extreme
put something back where it belongs	add a modifier to a constituent
put in the place of another; switch seemingly equivalent items	cause to change; make different; cause a transformation
take the place or move into the position of