The narrator of a story can be the author, protagonist, and the antagonist, but they can't be the reader.
Hello. You have not introduced the characters to which the question refers, which makes it impossible for your question to be answered accurately. However, I will try to help you in the best possible way.
The protagonist of a story is the main character and most of the time, represents "the good guy" of the story. The situations that are presented in the story revolve around this character and are ir goals and it struggles, which make up the story's purpose and develops all the elements that make up the plot. In a nutshell, the protagonist is the hero and the one who has the story told by the plot.
The antagonist, on the other hand, is the opposite of the protagonist, usually being constructed as the villain of the story. Antagonists have controversial goals and generally hinder the success of the protagosnista, directly or indirectly.
The preposition that is used in the given sentence above is the word "at", so the prepositional phrase is "at least once". Therefore, the words that are part of the prepositional phrase in this sentence are the words least and once. Hope this answers your question. Have a great day!
