Question 178·Easy·Form, Structure, and Sense
During the 1960s, astronomer Vera Rubin investigated the rotation curves of spiral galaxies and became one of the first ______ evidence for what is now known as dark matter.
Which choice completes the text so that it conforms to the conventions of Standard English?
For questions testing verb forms with set phrases, first locate the key structure around the blank (here, "one of the first"). Recall common patterns in standard usage—phrases like "the first/one of the first" are almost always followed by "to + verb" when explaining what someone did. Then, eliminate choices that break tense consistency with the rest of the sentence or that produce an unidiomatic or ungrammatical structure, and choose the one that fits both the pattern and the sentence’s meaning.
Hints
Focus on the phrase before the blank
Look closely at the words just before the blank: "became one of the first ______ evidence." Think about how English usually continues after "one of the first."
Think about verb form and time
The sentence is telling a story about the 1960s, so the main actions are in the past. Which verb form after "one of the first" fits naturally in that kind of past-tense description?
Recall a common pattern
Complete these in your head: "She was one of the first ___ arrive" and "They were the first ___ see it." What kind of verb phrase usually follows those expressions?
Step-by-step Explanation
Identify the core structure around the blank
Read the key part of the sentence:
"...Vera Rubin investigated the rotation curves of spiral galaxies and became one of the first ______ evidence for what is now known as dark matter."
The phrase "became one of the first" is followed by a blank that must smoothly introduce what she did (in relation to evidence).
Recognize the common pattern after "one of the first"
In Standard English, after phrases like "one of the first," "one of the last," or "the only one," we typically use to + verb (the infinitive) to show what that person did.
Examples:
- "She was one of the first to arrive."
- "They were among the first to discover this effect."
So we expect a structure like: "one of the first [astronomers] to ___ evidence."
Eliminate verb forms that don’t fit the pattern
Check each choice against the pattern "one of the first to + verb":
- "provides" is a present-tense verb and does not fit after "one of the first" in this past-tense narrative.
- "providing" is a participle and would make the phrase wordy and less direct: "one of the first providing evidence" is awkward.
- "provide" is a base verb and normally needs "to" after "one of the first" ("one of the first provide" is ungrammatical).
The only option that creates the standard and correct structure is "to provide", giving: "became one of the first to provide evidence for what is now known as dark matter."