Nouns with Adjectives and Adverbs

Nouns should be modified by adjectives, not by adverbs.

That man is the most sanctimoniously person I have ever met.

The adverb sanctimoniously is modifying the noun man; it should be changed to an adjective.

That man is the most sanctimonious person I have ever met.

While waiting for his life to unfold, Martin was an anxiously person; this changed after he met his wife.

While waiting for his life to unfold, Martin was an anxious person; this changed after he met his wife.

The dress was an ugly dress, perhaps the ugliest ever to exist.

Despite ending in ‑ly, the word ugly is an adjective and can be used to modify the noun dress.