keen vs intense

keen is a noun but intense is not a noun.

Word	Noun	Adjective	Verb	Adverb
keen	Yes	Yes	Yes	No
intense	No	Yes	No	No

keen (noun)	intense (noun)
a funeral lament sung with loud wailing

keen (adjective)	intense (adjective)
excellent	possessing or displaying a distinctive feature to a heightened degree
intense or sharp	(of color) having the highest saturation
having or demonstrating ability to recognize or draw fine distinctions	extremely sharp or severe
having a sharp cutting edge or point
painful as if caused by a sharp instrument

keen (verb)	intense (verb)
express grief verbally