obscenity vs do it

obscenity is a noun but do it is not a noun.

Word	Noun	Adjective	Verb	Adverb
obscenity	Yes	No	No	No
do it	No	No	Yes	No

obscenity (noun)	do it (noun)
an obscene act
the trait of behaving in an obscene manner
an offensive or indecent word or phrase

obscenity (verb)	do it (verb)
	have sexual intercourse with