Answer:
a - article
canvas - adjective
Explanation:
Articles are defined as the part of speech that primarily functions to indicate, specify, and limit a noun. While the adjectives function to modify a noun or the noun's referent. In the given sentence, the indefinite article 'a' helps in specifying the identity of the singular noun 'canvas sack' and 'canvas' is the adjective as it is modifying the noun 'sack' by providing detail about it that it is made up of 'woven fabric.'
