What is interesting about this novel is that the three blank words that Yunior omits to include at the end of the novel are not the only instance when this occurs. There are plenty of times when the narrator draws attention to various gaps in the story, or various "paginas blanco" (blank pages) in the narrative. These literary silences are recurrent motifs in the novel that seem to serve two purposes. Firstly, the reader is involved in working out their own meaning of the story. Secondly, it draws attention to the Trujillo regime and the way in which accounts were erased and deleted. Dashes are used therefore to draw attention to the way in which, even in spite of the best efforts of the narrator to fill the blank pages that Oscar left through his death, in the face of a repressive dictatorship, the truth will always be something that is so difficult to attain due to the manipulation that allows those who possess power to erase or twist the past. Note how this is referenced in the section this question refers to:
Before all hope died I used to have this stupid dream that shit could be saved, that we would be in bed together like the old times, with the fan on, the smoke from our weed drifting above us, and I'd finally try to say words that could have saved us.
_________ _________ _______.
The question as to what these words might have been haunts both the reader and Yunior, as he always wakes up before he shapes the vowels of these words. The reader is left to try to fill in the blanks and try and resurrect the truth from the partial accounts he or she is presented with.
Yunior leaves the 3 words blank as a constant symbol of the blank pages throughout the novel. The blank pages represent the dehumanization that Trejillo implemented as part of his dictatorship. If Trejillo didn't want someone around, he would make sure that he erased everything from their lives: their physical belongings and their own family. Yunior was at a loss of words which is represented by those pages.