A modifier question tests whether an opening describing phrase points to the right person or thing. If the phrase says something was done, ask who or what it was done to. The main noun after the comma must be what the phrase describes. Name that person or thing, then find each choice’s main noun and read to the end. Extra details can delay the main noun, so look past them rather than trusting how natural a sentence sounds.
Hints
- Hint 1
Ask what the opening phrase says was built. It describes something without naming it.
- Hint 2
Find the main noun in each completed sentence. Does that noun answer your question about what was built?
Step-by-step
Match the description to its noun
Step 1Identify what the opening describes
The sentence starts with Built on a foundation of innovative engineering, but this phrase doesn't name what was built. Who or what does it describe? It says something was built, so we're looking for the thing built, not whoever built it. An opening describing phrase must describe the main noun that follows its comma, so that's what we need to check in each completed sentence.
- Step 2
Find the main noun past extra words
Which main noun do the different starts give us? The version starting with completed in 1910 reaches engineers after another describing phrase, while engineers completed starts with engineers right away. In the version starting with in 1910, both the date and the phrase about building come before the main noun, engineers. Those starts make Built on a foundation of innovative engineering describe the engineers themselves, rather than the structure they built.
- Step 3
Read the railway sentence through
The version beginning the Trans-Andean Railway puts the built structure first. Does the extra date change that noun or disrupt the rest of the sentence? The phrase completed in 1910 sits between commas as extra information, so setting it aside leaves the railway as the subject of dramatically reduced travel times. The completed sentence says the railway was built and reduced travel times, with both descriptions attached to the same thing. Choice B.