Is industrious an adverb

No.

An adverb adds information about a verb.

Example sentences:

* "That worker is very industrious." ... It is the person that is industrious, so industrious is an adjective. An adjective gives additional information about a noun. * "He works industriously." This tells us how he 'works'. 'Work' is a verb. A Word that tells us more about a verb is an adverb, so industriously is an adverb.