The city of Pompeii, which was buried in ash following the eruption of Mount Vesuvius in 79 CE, continues to...

Sentence Structure

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!

• The city of Pompeii,
  • which was buried in ash
    • following the eruption of Mount Vesuvius in 79 CE,
• continues to be studied by archaeologists.

• Unfortunately,
  • as ______ attest,
    • [researchers (?) Roberto Scandone and Christopher Kilburn (?)]
    • archaeological excavations
      • have disrupted ash deposits at the site,
        • causing valuable information about the eruption to be lost.

Understanding the Meaning

Let's start from the beginning to get the full context.

The first sentence tells us:

• The city of Pompeii was buried in ash when Mount Vesuvius erupted in 79 CE
• Archaeologists continue to study it today

Now the second sentence:

• "Unfortunately, as ______ attest..."

This is where we have the blank. Let's look at the choices:

• Choice A: researchers, Roberto Scandone and Christopher Kilburn,
• Choice B: researchers, Roberto Scandone and Christopher Kilburn
• Choice C: researchers Roberto Scandone and Christopher Kilburn
• Choice D: researchers Roberto Scandone, and Christopher Kilburn

The choices are showing us different comma placements around these names. To see what works here, let's read the rest of the sentence and understand what it's saying!

The sentence continues:

• "archaeological excavations have disrupted ash deposits at the site, causing valuable information about the eruption to be lost."

So the complete meaning is:

• Two specific researchers (Roberto Scandone and Christopher Kilburn) are confirming/testifying to a problem
• The problem is that archaeological excavations have messed up the ash layers at Pompeii
• This disruption has caused us to lose valuable information about how the eruption happened

What do we notice about the structure here?

The phrase "as researchers Roberto Scandone and Christopher Kilburn attest" means "according to these two specific researchers."

• The word "researchers" is a general term
• The names "Roberto Scandone and Christopher Kilburn" tell us exactly WHICH researchers we're talking about
  • These names are essential - they identify the specific people
  • Without the names, we'd just have "as researchers attest" which is too vague
  • The names aren't extra information we could remove - they're necessary to specify who these researchers are

When names are essential identifiers like this - when they tell us which specific people we're referring to - we don't use commas to set them off.

Also notice: we're listing two names connected by "and"

• "Roberto Scandone and Christopher Kilburn"
• With just two items, we don't put a comma before "and"
• Commas in lists are only for three or more items

So we need: researchers Roberto Scandone and Christopher Kilburn

The correct answer is Choice C.

GRAMMAR CONCEPT APPLIED

Essential vs. Nonessential Information: When to Use Commas with Names

When a general noun is followed by specific names, whether you use commas depends on whether those names are essential to identify who/what you're talking about:

Essential identifiers (NO commas):

• When the names specify WHICH specific people from a larger group
• The researcher Roberto Scandone made a discovery
  • "Roberto Scandone" is essential - it tells us which researcher
• The poets Byron and Shelley influenced Romanticism
  • The names specify which poets

Nonessential information (USE commas):

• When the person is already clearly identified, and the name adds extra info
• My only colleague, Roberto, agreed with me
  • "Only colleague" already identifies who - just one person
  • The name "Roberto" is bonus information
• The author, writing under a pen name, became famous
  • The description is extra detail, not essential identification

In this question:

• "researchers Roberto Scandone and Christopher Kilburn" uses no commas
• The names are essential - they identify WHICH specific researchers from all possible researchers
• Without the names, "as researchers attest" would be too vague

Bonus rule: When listing two items, don't use a comma before "and"

• Roberto Scandone and Christopher Kilburn (correct)
• Roberto Scandone, and Christopher Kilburn (incorrect)
• Commas in lists are only needed with three or more items