Although migrations of the monarch butterfly _____ thousands of miles, individual butterflies typically complete only one leg of the entire...

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

• Although migrations of the monarch butterfly
• [?] thousands of miles,
• individual butterflies typically complete only one leg of the entire journey.

Understanding the Meaning

Let's start reading from the beginning:

'Although migrations of the monarch butterfly...'

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

• 'migrations of the monarch butterfly _____ thousands of miles'

Let's look at our choices:

• A. spans (singular)
• B. is spanning (singular)
• C. span (plural)
• D. has spanned (singular)

What do we notice about the structure here?

• The subject of this part is 'migrations' - that's the thing doing the action
  • 'migrations' is plural
• 'of the monarch butterfly' is just a descriptive phrase
  • It tells us WHICH migrations we're talking about
  • But it's not the subject itself
• The word 'butterfly' appears right before the blank
  • This might tempt us to use a singular verb
  • BUT 'butterfly' is not the subject - it's part of the descriptive phrase
• The verb needs to match 'migrations' (plural), not 'butterfly' (singular)

So we need: span - the plural form that agrees with 'migrations.'

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

'individual butterflies typically complete only one leg of the entire journey.'

This is creating an interesting contrast:

• The migrations themselves span thousands of miles (the whole journey is huge)
• BUT each individual butterfly only completes one portion of that journey
• So even though the migration as a whole covers thousands of miles, no single butterfly makes the entire trip

The correct answer is C: span

Grammar Concept Applied

Making Verbs Agree with Subjects When There's a Phrase In Between

When a descriptive phrase comes between the subject and verb, you need to identify the true subject and make sure the verb agrees with it - not with a word in the phrase that happens to be closer to the verb.

The pattern:

• Subject + descriptive phrase + Verb
• The verb must agree with the subject, even if other nouns appear in between

Example 1:

• "The box of chocolates are on the table."
• "The box of chocolates is on the table."
• Subject: "box" (singular)
• Descriptive phrase: "of chocolates"
• Verb must match "box": is (singular)

Example 2:

• "The students in the classroom works quietly."
• "The students in the classroom work quietly."
• Subject: "students" (plural)
• Descriptive phrase: "in the classroom"
• Verb must match "students": work (plural)

In our question:

• Subject: "migrations" (plural)
• Descriptive phrase: "of the monarch butterfly" (contains singular "butterfly")
• The verb must match "migrations": span (plural)
• Even though "butterfly" is singular and appears right before the verb, it's not the subject

The key is to ask yourself: "What is actually doing the action?" In this sentence, what's spanning thousands of miles? The migrations - plural. So we need the plural verb "span."