Hegra is an archaeological site in present-day Saudi Arabia and was the second largest city of the Nabataean Kingdom (fourth...

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!

Sentence Structure

• Hegra is an archaeological site in present-day Saudi Arabia
  • and was the second largest city of the Nabataean Kingdom
    • (fourth century BCE to first century CE).
• Archaeologist Laila Nehmé recently traveled to Hegra
  • to study its ancient tombs [?] built
    • into the rocky outcrops of a vast desert,
  • these burial chambers seem to blend seamlessly with nature.

Understanding the Meaning

The passage starts by giving us background about Hegra:

• It's an archaeological site in Saudi Arabia
• It was a major city in the ancient Nabataean Kingdom

Then we learn about a recent visit:

• Archaeologist Laila Nehmé traveled there
• Her purpose: to study its ancient tombs

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

• A. tombs. Built (period, starts new sentence)
• B. tombs, built (comma, continues same sentence)
• C. tombs and built (uses "and")
• D. tombs built (no punctuation)

To see what works here, let's read the rest and understand what it's saying!

The text continues:

• "built into the rocky outcrops of a vast desert"
  • This describes WHERE the tombs are located - they're carved/built into rocky desert formations
• Then: "these burial chambers seem to blend seamlessly with nature"
  • "These burial chambers" = another way of referring to the tombs
  • This is telling us something about them: they blend with nature
  • This is a complete thought with its own subject (these burial chambers) and verb (seem)

What do we notice about the structure here?

• "These burial chambers seem to blend seamlessly with nature" is a complete independent thought
  • It could stand alone as its own sentence
• "Built into the rocky outcrops of a vast desert" is a descriptive phrase
  • It tells us about the burial chambers
  • When this kind of describing phrase starts a sentence and is followed by a comma, it describes what comes right after that comma

So we need to create two separate sentences:

• Sentence 1 ends: "...to study its ancient tombs."
• Sentence 2 begins: "Built into the rocky outcrops of a vast desert, these burial chambers seem to blend seamlessly with nature."
  • The phrase "Built into..." describes the burial chambers
  • This structure (describing phrase, comma, main clause) is a complete and correct sentence

The correct answer is A: tombs. Built

GRAMMAR CONCEPT APPLIED

Separating Independent Clauses and Using Introductory Descriptive Phrases

When you have a complete independent thought (a clause with its own subject and verb that could stand alone as a sentence), you need to separate it properly from what comes before. One way to do this is with a period, creating two distinct sentences.

Pattern 1 - Ending one complete thought:

• "Archaeologist Laila Nehmé recently traveled to Hegra to study its ancient tombs."
• Complete subject: "Archaeologist Laila Nehmé"
• Complete verb: "traveled"
• This stands alone perfectly

Pattern 2 - Starting a new sentence with a descriptive phrase:

• "Built into the rocky outcrops of a vast desert, these burial chambers seem to blend seamlessly with nature."
• "Built into the rocky outcrops of a vast desert" = introductory descriptive phrase (called a participial phrase in grammar terms)
• Comma after the introductory phrase
• "These burial chambers seem to blend seamlessly with nature" = the main clause
• The introductory phrase describes what comes right after the comma

Why this matters:

When you have two independent clauses, you CANNOT just use a comma to connect them - that creates a comma splice. You need:

• A period (two sentences) ✓
• A semicolon
• A comma + coordinating conjunction (and, but, or, etc.)

In this question, using the period creates two properly structured sentences, with the second sentence effectively using an introductory descriptive phrase to paint a vivid picture of these ancient tombs.