harshen vs modify

harshen and modify both are verbs.

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

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

Other hypernyms of harshen include alter, change.

harshen (verb)	modify (verb)
make harsh or harsher	make less severe or harsh or extreme
	add a modifier to a constituent
	cause to change; make different; cause a transformation