In 1903, environmentalist John Muir guided President Theodore Roosevelt on a scenic, sprawling trip through California's Yosemite Valley. Upon returni...

Sentence Structure

• In 1903,
• environmentalist John Muir
  • guided President Theodore Roosevelt
    • on a scenic, sprawling trip
      • through California's Yosemite Valley.
• Upon returning from the three-day excursion,
• Roosevelt [?]
  • to conserve the nation's wilderness areas,
    • a vow
      • he upheld
        • for his remaining six years in office.

Understanding the Meaning

Let's start reading from the beginning:

The first sentence tells us:

• In 1903, John Muir (an environmentalist)
  • guided President Roosevelt on a trip through Yosemite Valley.

This establishes we're talking about historical events from 1903.

The second sentence continues the story:

• "Upon returning from the three-day excursion"
  • So after they got back from this trip

Now here's where we need to fill in the blank:

• "Roosevelt ______ to conserve the nation's wilderness areas"

Let's look at our choices:

• A. is vowing (present progressive - happening now)
• B. vowed (past tense)
• C. will vow (future tense)
• D. vows (present tense)

What do we know so far?

• The passage starts with "In 1903" - a specific time in the past
• The first sentence uses "guided" - past tense
• We're reading about what Roosevelt did after returning from a historical trip

So we need past tense to match this historical narrative: vowed is correct.

Now let's read the rest to see the complete picture:

• "a vow he upheld for his remaining six years in office"
  • This confirms Roosevelt already kept this promise during the rest of his presidency
  • "upheld" is also past tense
  • This all happened in the past - it's history we're recounting

What do we notice about the structure here?

• The entire passage is a historical narrative set in 1903
• All the verbs describing these events are in past tense:
  • "guided" (what Muir did)
  • "upheld" (what Roosevelt did with the vow)
• The blank describes what Roosevelt did upon returning - another past action

The correct answer is B. vowed because this is a historical event that happened in 1903, and it needs to match the past tense established throughout the passage.

GRAMMAR CONCEPT APPLIED

Maintaining Verb Tense Consistency in Narratives

When you're writing about events, all verbs describing actions within the same time frame should use the same tense. Time markers and other verbs in the passage help you identify what tense to use.

For past narratives (like historical events):

• Time marker present: "In 1903" signals we're in the past
• Other verbs: "guided" (past), "upheld" (past)
• Therefore: Any verb describing actions in this same time period → past tense
• In this question: "vowed" correctly matches the past time frame

The pattern to follow:

1. Look for time markers (dates, "yesterday," "last year," etc.)
2. Notice what tense the other verbs use
3. Check that events follow a logical sequence
4. Make sure your verb matches the established time frame

Why this matters:

• "Roosevelt vowed" (1903) → "he upheld" (for six years after) = Logical past sequence ✓
• "Roosevelt will vow" (future) → "he upheld" (past) = Illogical timeline ✗

In this question, the clear past markers ("In 1903," "guided," "upheld") and the completed time reference ("his remaining six years in office") all signal that we're recounting finished historical events, so past tense is required throughout.