sympathise vs empathize

sympathise and empathize both are verbs.

Word	Noun	Adjective	Verb	Adverb
sympathise	No	No	Yes	No
empathize	No	No	Yes	No

As verbs, sympathise and empathize are synonyms defined as:

Other synonyms of sympathise include empathise, sympathize, understand.

sympathise (verb)	empathize (verb)
be understanding of	be understanding of
to feel or express sympathy or compassion
share the feelings of; understand the sentiments of