WAEC - English Language (1997 - No. 52)
From the words or group of words labelled A to D, choose the one that best completes each of the following sentences.
That uncle of............ought to see you through this.
your
your's
yours
yours'
Explication
The word "yours" is a pronoun that shows possessiveness, but it's used independently as a post-modifier.
So in the sentence:
"That uncle of yours ought to see you through this."
The word "yours" is correct because it comes after a preposition ("uncle") and functions as a possessive pronoun.