neck vs do it

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

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

neck (noun)	do it (noun)
an opening in a garment for the neck of the wearer; a part of the garment near the wearer's neck
a narrow part of an artifact that resembles a neck in position or form
the part of an organism (human or animal) that connects the head to the rest of the body
a cut of meat from the neck of an animal
a narrow elongated projecting strip of land

neck (verb)	do it (verb)
kiss, embrace, or fondle with sexual passion	have sexual intercourse with