AP English Literature Explain the Function of Comparison is the skill of identifying comparisons in a text and explaining what those comparisons do for meaning. You spot a simile, metaphor, personification, or allusion, then show how it moves the text from literal description into figurative meaning. The goal is not just naming the device but explaining its function: what idea, feeling, or interpretation the comparison creates.

This skill is Skill Category 6 in the course, and it makes up about 10 to 13 percent of the multiple-choice section. It connects directly to the Figurative Language big idea: comparisons, representations, and associations shift meaning from the literal to the figurative and invite readers to interpret a text.

What Explain the Function of Comparison Means

Comparison is one of the main ways literature builds figurative meaning. When a writer compares one thing to another, they ask you to carry traits from one idea over to another. A storm becomes grief. A clock becomes a heartbeat. A character becomes a modern Odysseus.

"Function" is the key word. Function means the effect or purpose, not the label. You are answering questions like:

What two things are being compared?
What traits transfer from one to the other?
What new meaning, mood, or insight does that transfer create?
How does that meaning connect to the larger text?

Naming a metaphor earns nothing on its own. Explaining what the metaphor does for the reader's interpretation is where the skill lives.

What This Skill Requires

To explain the function of a comparison well, you need to:

Identify the comparison and the two elements being linked.
Distinguish literal from figurative so you do not read a figurative line as a fact.
Analyze the shared traits that make the comparison work.
Connect the comparison to meaning, such as theme, tone, character, or the reader's interpretation.

A reliable sentence frame for practice: "By comparing X to Y, the writer suggests Z, which shapes the reader's understanding of ___." Treat this as practical advice, not an official rule.

Subskills You Need

6.A: Identify and Explain the Function of a Simile

A simile compares two things using "like" or "as."

Example: "Her patience was thin as paper."
The comparison links patience to paper. Shared trait: fragility and the sense that it could tear at any moment.
Function: the simile signals that the character is close to a breaking point, building tension before a likely outburst.

When you analyze a simile, name the two things, then explain what quality transfers and why it matters.

6.B: Identify and Explain the Function of a Metaphor

A metaphor compares two things directly, without "like" or "as." It states that one thing is another.

Example: "The classroom was a pressure cooker before exams."
The comparison equates the classroom with a sealed, heated container.
Function: the metaphor conveys mounting stress and the danger of an emotional release, without saying "everyone felt stressed."

Watch for extended metaphors, where a single comparison runs across many lines or a whole poem. These build meaning through related images that work together.

6.C: Identify and Explain the Function of Personification

Personification gives human qualities to nonhuman things such as objects, animals, or abstractions.

Example: "The wind whispered through the empty house."
Wind cannot whisper, so a human action is mapped onto a natural force.
Function: "whispered" creates an intimate, almost secretive mood and makes the empty house feel watched or haunted.

When analyzing personification, ask what human trait is being assigned and what mood or idea that human framing creates.

6.D: Identify and Explain the Function of an Allusion

An allusion is a reference to another text, person, event, or work, often historical, literary, mythological, or biblical.

Example: Calling a long, troubled journey home "an Odyssey."
The comparison links the character's trip to Odysseus's mythic voyage.
Function: the allusion adds scale and struggle, suggesting the journey is epic, full of obstacles, and meaningful beyond its surface.

Allusions work only if you recognize the source's associations. Explain what the referenced thing is known for, then show how those associations transfer into the current text.

How It Shows Up on the AP Exam

Multiple-choice section: Skill Category 6 is about 10 to 13 percent of multiple-choice questions. Expect questions that ask you to identify a comparison, interpret what it suggests, or explain its effect on tone or meaning. These appear in both poetry and prose passages drawn from a range of time periods, with more 20th-century and contemporary texts.

Free-response section: Comparison shows up across all three essays.

Poetry Analysis (FRQ 1): Poems often build their argument through simile, metaphor, personification, and allusion. Strong responses explain how those comparisons shape meaning.
Prose Fiction Analysis (FRQ 2): Narrative passages use comparison to develop character, setting, and tone.
Literary Argument (FRQ 3): You can use comparison as evidence when explaining how a writer develops an interpretation across a full work.

In every essay, evidence plus commentary matters. Quoting a metaphor is evidence. Explaining its function is the commentary that earns credit.

Examples Across the Course

These examples show how comparison appears in different course areas. Texts vary by classroom, so these are illustrative.

Poetry (Intro to Poetry topics): A speaker compares a lost friendship to a "closed door." The metaphor turns an abstract feeling into a physical barrier, signaling finality and exclusion.
Extended metaphor in poetry (Structure and Figurative Language): A poem sustains a comparison between a relationship and a sailing voyage across multiple stanzas, using related images of wind, anchors, and storms to track the relationship's changing course.
Personification and allusion in poetry: A poem might personify Death as a patient companion, or allude to a mythological figure to deepen a single image. Both ask you to interpret what associations the comparison carries.
Prose fiction (Complexities in Short Fiction): A narrator describes a cold father as "a locked vault." The metaphor characterizes him as guarded and emotionally inaccessible, shaping how you read his relationships.
Longer works and drama (Literary Techniques in Longer Works): An allusion to a biblical or classical figure can frame a character's choices as part of a larger moral or cultural pattern, adding weight to a single decision.

Notice the pattern: in each case you move from spotting the device to explaining the figurative meaning it produces.

How to Practice Explain the Function of Comparison

Always name both halves. Write out "X compared to Y" before you interpret. You cannot explain function without identifying the two elements.
List the shared traits. Ask what qualities transfer from Y to X. The transfer is the meaning.
Push past the label. After you say "this is a metaphor," force yourself to write a "so what" sentence about its effect.
Check literal versus figurative. If a line seems strange taken literally, it is probably figurative. Read it that way.
Practice with short passages. Take one stanza or one paragraph and find every comparison, then explain each one in a sentence.
Build a frame. Use "By comparing ___ to ___, the writer suggests ___." Practical advice, not an official requirement.

Common Mistakes

Naming without explaining. Writing "the author uses a simile here" with no analysis of its effect. Always add the function.
Reading figurative language literally. Treating "her heart was stone" as a medical claim rather than a statement about emotional coldness.
Ignoring the source of an allusion. Mentioning an allusion without explaining what the referenced text or figure is known for, so the comparison has no payoff.
Confusing simile and metaphor. Remember the test: similes use "like" or "as," metaphors state the comparison directly.
Stopping at one image in an extended metaphor. Missing how related images work together across lines or stanzas.
Forcing personification. Not every vivid verb is personification. The nonhuman thing must take on a genuinely human trait.

Quick Review

This skill is Skill Category 6, about 10 to 13 percent of multiple-choice questions.
Function over label: identify the comparison, then explain what it does for meaning.
6.A Simile: comparison using "like" or "as."
6.B Metaphor: direct comparison, including extended metaphors that run across a text.
6.C Personification: human qualities given to nonhuman things.
6.D Allusion: reference to another text, person, event, or work, carrying its associations into the current text.
Core move: name both halves of the comparison, identify the shared traits, then explain the figurative meaning and how it connects to tone, character, or theme.
Comparison appears in all three FRQs and in both poetry and prose multiple-choice passages.