A banjo string
The simile "it pinged like a banjo string" is used to describe the author's torn hamstring. This simile is used to underline the severity of the injury. The author is equating the sensation of the hamstring injury to the twang of a banjo string, which produces a piercing, vibrating sound that is meant to represent the author's acute anguish. The analogy is also used to express the author's annoyance and sadness at being injured and unable to play his favored position in softball. The sound of a banjo string evokes a sensation of longing and nostalgia, which mirrors the author's feelings of loss and regret at being neglected.
The back stairs
The metaphor "Those who have any [power] at all have to use the back stairs" implies that individuals with power must employ covert or subversive means to attain their objectives. This is because they are unable to use the more direct and open approaches associated with individuals in positions of control. Using the "back stairs" implies that these people must take a less obvious path to get what they seek, one that is less visible and may include some type of deception or manipulation. This metaphor can be construed to suggest that those who lack authority must take shortcuts or alternative routes to get what they want as the traditional paths of power are not available to them.
Gigged like a frog
The simile "I was gigged like a frog" compares the protagonist's experience with a spiral notebook stuck in his nostril to a frog being captured with a spear-like weapon. The simile implies that the protagonist was in a vulnerable position, unable to remove himself from his difficult situation. It also implies that he felt powerless and embarrassed since he was at the whim of someone else, as frogs are when they get gigged. The analogy to a giggled frog highlights the discomfort of the circumstance as well as the protagonist's feelings of humiliation and shock.
Silence
The phrase "We've worked long and hard to achieve this silence" refers to the narrator's relationship with his wife. The author implies that the pair have worked hard to understand and communicate with one another without the need for words. This metaphor emphasizes that silence, rather than words, can be used to communicate and understand. It is a testimonial to the couple's marital strength that they can comprehend each other without using words. The metaphor also implies that the pair has a high level of mutual trust and understanding. They are familiar enough with one another that they don't need to argue or explain things in great detail.
Death camp dwellers
Finny's students are compared to "death camp dwellers" in this line, implying that his teaching style is repressive and too demanding. It indicates that Finny's students feel dread and despair as if they were in a prison camp, as a result of the severe homework and tight attendance regime established by Finny. This comparison highlights the extreme contrast between Finny's formerly outgoing and carefree manner while he was off his medicine and his current demeanor, which is defined by arrogance and tedium. The comparison emphasizes Finny's unpleasant classroom environment and his students' sense of desperation.
A violin
The speaker compares her mother's paternal manipulation to playing the violin. This comparison implies that the speaker's mother has a lot of power over her father. A violinist is a musician who has control over the instrument's strings, determining their pitch and the song that they play. Similarly, the mother wields considerable power over the father, utilizing her influence to influence and steer his decisions and behaviors. This simile says that the mother has a profound understanding of her husband, which she employs in the same manner as a musician who employs their knowledge of the instrument to create beautiful music.
