In 2009, researchers determined that pottery fragments from a cave in China were close to 18,000 years old. These are...

Sentence Structure

Sentence 1:

• In 2009,
• researchers
  • determined
    • that pottery fragments from a cave in China
      • were close to 18,000 years old.

Sentence 2:

• These
  • are some of the oldest pieces [?] of pottery ever found.

Understanding the Meaning

Let's read from the beginning to understand what's happening:

The first sentence tells us:

• In 2009, researchers determined that pottery fragments from a cave in China were close to 18,000 years old.
  • So we have a discovery of very ancient pottery fragments

Now the second sentence:

• "These are some of the oldest"
  • "These" refers back to those pottery fragments
  • They're among the oldest of something

This is where we have the blank:

• "pieces [?] of pottery ever found"

Let's look at the choices:

• A adds a colon after "pieces"
• B adds a comma after "pieces"
• C has no punctuation after "pieces"
• D adds a dash after "pieces"

To see what works here, let's understand what this phrase is actually saying!

The complete phrase is: "the oldest pieces of pottery ever found"

What do we notice about the structure here?

• "pieces of pottery" works as a single unit
  • "of pottery" tells us what kind of pieces we're talking about
  • It answers the question: pieces of what?

• This "of pottery" part is essential to the meaning
  • Without it, we'd just have "pieces" - but pieces of what?
  • We NEED "of pottery" to know what these pieces are

• When describing information is essential (not extra), it flows directly without punctuation
  • "of pottery" isn't bonus information we're adding
  • It's a necessary part of identifying what the pieces are

So we need: no punctuation between "pieces" and "of pottery" - they flow together as one complete phrase.

The correct answer is C.

GRAMMAR CONCEPT APPLIED

Essential Prepositional Phrases: When NOT to Use Punctuation

When you have a noun followed by a prepositional phrase (a phrase starting with words like "of," "in," "on," "with") that defines or specifies that noun, no punctuation separates them. The prepositional phrase is essential to the meaning:

Pattern: Noun + of + specifying information (no punctuation between them)

Examples:

• "a cup of coffee" (not: a cup, of coffee)
• "the cost of living" (not: the cost, of living)
• "pieces of pottery" (not: pieces, of pottery)

In our question:

• Noun: pieces
• Essential prepositional phrase: of pottery
• Why it's essential: Without "of pottery," we don't know what kind of pieces - the phrase is necessary to complete the meaning
• Result: No punctuation between them - they flow together as one complete noun phrase

This is different from extra, non-essential information (called non-restrictive information in grammar terms), which DOES get set off by commas or dashes. For example: "The fragments, discovered in 2009, were very old." Here, "discovered in 2009" is bonus information that could be removed, so it gets commas.