shallow vs ankle-deep

shallow is a noun but ankle-deep is not a noun.

Word	Noun	Adjective	Verb	Adverb
shallow	Yes	Yes	Yes	No
ankle-deep	No	Yes	No	No

shallow (noun)	ankle-deep (noun)
a stretch of shallow water

shallow (adjective)	ankle-deep (adjective)
lacking physical depth; having little spatial extension downward or inward from an outer surface or backward or outward from a center	coming only to the ankle or knee
not deep or strong; not affecting one deeply
lacking depth of intellect or knowledge; concerned only with what is obvious

shallow (verb)	ankle-deep (verb)
become shallow
make shallow