This flexible little French word can function as adverb, adjective, and/or preposition. Let’s take the definitions in order, shall we” As an adverb it means with regard to the present topic or at an appropriate time. As an adjective it means relevant and applicable. As a preposition it means concerning and with regard to, and you’d use it with the word “of”, as in “apropos of…” We’ll use the adjective version in our example sentence.
EXAMPLE: In light of the hellish project that she had just lived through, Violet felt that her words of warning on the firm’s existing contractual agreement were quite apropos.