sustainable vs sustain

sustainable is an adjective but sustain is not an adjective.

Word	Noun	Adjective	Verb	Adverb
sustainable	No	Yes	No	No
sustain	No	No	Yes	No

sustainable (adjective)	sustain (adjective)
capable of being sustained

sustainable (verb)	sustain (verb)
	undergo (as of injuries and illnesses)
	establish or strengthen as with new evidence or facts
	admit as valid
	supply with necessities and support
	provide with nourishment
	be the physical support of; carry the weight of
	lengthen or extend in duration or space