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 <u>'canvas' is the adjective as it is modifying the noun 'sack' by providing detail about it that it is made up of 'woven fabric</u>.'
