In 2012, researchers at the Large Hadron Collider detected unusual energy signatures in their particle collision experiments and _____ the...

Sentence Structure

• In 2012,
  • researchers at the Large Hadron Collider
    • detected unusual energy signatures
      • in their particle collision experiments
    • and [?] the existence of the Higgs boson,
      • confirming a theory
        • that physicists had proposed nearly fifty years earlier.

Understanding the Meaning

Let's start reading from the beginning:

In 2012, researchers at the Large Hadron Collider did something:

• they 'detected unusual energy signatures in their particle collision experiments'
  • So they found some unusual energy patterns when they were smashing particles together

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

• 'and _____ the existence of the Higgs boson'

Let's look at our choices:

• A. to confirm (infinitive form)
• B. confirmed (past tense)
• C. confirming (participle form)
• D. to have confirmed (perfect infinitive)

What do we notice about the structure here?

• We have two actions connected by 'and' that the same subject (researchers) performed:
  • First action: 'detected' unusual energy signatures
  • Second action: [blank] the existence of the Higgs boson

• When you connect two verbs with 'and' that share the same subject, they need to match in form - this keeps them parallel
  • 'Detected' is past tense
  • So the second verb should also be past tense

So we need: confirmed (past tense to match 'detected')

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

• 'confirming a theory that physicists had proposed nearly fifty years earlier'

This final part is telling us the significance of what the researchers did:

• By detecting these signatures and confirming the Higgs boson's existence, they were confirming (proving true) a theory
• This theory was something physicists had come up with almost fifty years before 2012

So the complete meaning: In 2012, researchers detected unusual patterns and confirmed the Higgs boson exists - and by doing this, they proved a fifty-year-old theory was correct.

The correct answer is B. confirmed because it maintains parallel structure with 'detected' - both actions the researchers performed need to be in the same verb form.

GRAMMAR CONCEPT APPLIED

Keeping Verbs Parallel in Compound Predicates

When you have two or more verbs connected by coordinating conjunctions like "and," "or," or "but" that share the same subject, those verbs need to be in the same form and tense. This is called parallel structure (or parallelism in grammar terms).

The Pattern:

• Subject + Verb₁ (form/tense) + and + Verb₂ (matching form/tense)

Example 1:

• Correct: "The scientist conducted the experiment and analyzed the results."
  • Both verbs in past tense
• Incorrect: "The scientist conducted the experiment and to analyze the results."
  • Doesn't match (past tense + infinitive)

Example 2:

• Correct: "The students study biology and take chemistry classes."
  • Both verbs in present tense
• Incorrect: "The students study biology and taking chemistry classes."
  • Doesn't match (present tense + participle)

In our question:

• Researchers detected [past tense] unusual energy signatures and confirmed [past tense] the existence of the Higgs boson
  • Both verbs describe actions the researchers performed in 2012, so they both need to be past tense to maintain parallel structure