Margaret Bourke-White became the first female photojournalist for Life magazine in 1936, and her groundbreaking work during World War II...

Let's begin by understanding the meaning of this sentence. We'll use our understanding of pause points and segment the sentence as shown - understanding and assimilating the meaning of each segment bit by bit!

Sentence Structure

• Margaret Bourke-White became the first female photojournalist for Life magazine in 1936,
  • and her groundbreaking work during World War II
    • established _____ as one of the most influential visual documentarians
      • of the twentieth century.

• The blank needs:
  • "her" (common to all choices)
  • [? punctuation around descriptive phrase ?]

Understanding the Meaning

Let's start reading from the beginning:

Margaret Bourke-White became the first female photojournalist for Life magazine in 1936,

• This introduces us to Margaret Bourke-White and tells us she was a groundbreaking photojournalist - the first woman to hold this position at Life magazine.

and her groundbreaking work during World War II established...

• Now we're learning about her work during World War II and how it established something.

This is where we have the blank. Let's look at the choices:

• All choices start with "her" (referring back to Margaret Bourke-White)
• All include the phrase "a photographer who captured both the brutality of war and the resilience of ordinary people"
• What varies is the PUNCTUATION around this descriptive phrase

To see what works here, let's read the rest of the sentence and understand what it's saying!

The sentence continues: "as one of the most influential visual documentarians of the twentieth century."

Now let's understand what this complete sentence is telling us:

• The main sentence structure is:
  • Subject: "her groundbreaking work during World War II"
  • Verb: "established"
  • Object: "her"
  • Complement: "as one of the most influential visual documentarians of the twentieth century"

• If we read just the main parts: "her groundbreaking work...established her as one of the most influential visual documentarians"
  • This is a complete thought on its own

• The phrase "a photographer who captured both the brutality of war and the resilience of ordinary people" is:
  • Extra descriptive information about Margaret Bourke-White
  • Being inserted into the middle of the main sentence
  • Like an aside that gives us more detail about who she was

What do we notice about the structure here?

• When you insert a descriptive phrase into the middle of a sentence, you need to set it off with punctuation:
  • You need punctuation to open the interruption (before "a photographer")
  • You need punctuation to close the interruption (after "ordinary people")
  • The punctuation on both sides needs to MATCH

• Looking at our choices:
  • Choice A: her—phrase— (dash before, dash after) ✓ MATCHES
  • Choice B: her, phrase (comma before, nothing after) ✗ Doesn't close
  • Choice C: her—phrase, (dash before, comma in wrong spot) ✗ Doesn't match
  • Choice D: her, phrase— (comma before, dash after, confusing) ✗ Doesn't match

The correct answer is Choice A. We need matching dashes on both sides to properly set off this descriptive phrase from the main sentence flow. The dashes create a clear interruption: "established her—[descriptive information]—as one of the most influential visual documentarians."

GRAMMAR CONCEPT APPLIED

Setting Off Interrupting Descriptive Phrases with Matching Punctuation

When you insert a descriptive phrase into the middle of a sentence to provide additional information, you must set it off with matching punctuation on both sides (called setting off a nonessential element in grammar terms). You have three options:

Option 1: Two commas

• Main sentence: The scientist announced the discovery
• With interruption: The scientist, a researcher who had worked for decades on the problem, announced the discovery
• Opens with comma after "scientist"
• Closes with comma after "problem"

Option 2: Two dashes

• Main sentence: The discovery changed everything
• With interruption: The discovery—a finding that contradicted previous theories—changed everything
• Opens with dash after "discovery"
• Closes with dash after "theories"

Option 3: Two parentheses

• Main sentence: The results were remarkable
• With interruption: The results (the culmination of years of research) were remarkable
• Opens with opening parenthesis
• Closes with closing parenthesis

Key principle: The interrupting phrase must be bracketed on BOTH sides with MATCHING punctuation. You can't mix types (like comma and dash), and you can't leave one side open.

In our question: "her groundbreaking work...established her—a photographer who captured both the brutality of war and the resilience of ordinary people—as one of the most influential visual documentarians"

• The phrase "a photographer who captured..." interrupts the main flow
• Dashes on both sides properly set it off
• The sentence remains complete if you remove the interruption: "established her as one of the most influential visual documentarians" ✓

Why dashes work well here: Dashes are particularly effective for longer interrupting phrases or when you want to give the additional information emphasis. In this case, the descriptive phrase is substantial and provides important context about Margaret Bourke-White's work, so dashes appropriately signal its significance.