Researchers studying the 'terra-cotta army,' the thousands of life-size statues of warriors found interred near the tomb of Emperor Qin...

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

• Researchers studying the 'terra-cotta army,'
  • the thousands of life-size statues of warriors
    • found interred near the tomb of Emperor Qin Shi Huang of China,
• were shocked to realize that
  • the shape of each statue's ears,
    • like the shape of each person's ears,
  • [?] unique.

Understanding the Meaning

Let's start reading from the beginning:

Researchers were studying the 'terra-cotta army' –

• This is that famous archaeological discovery of thousands of warrior statues.
• The sentence gives us more detail: 'the thousands of life-size statues of warriors found interred near the tomb of Emperor Qin Shi Huang of China.'

These researchers 'were shocked to realize that' – they discovered something surprising.

What was surprising? The sentence tells us in a subordinate clause:

• 'the shape of each statue's ears, like the shape of each person's ears, ______ unique.'

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

• are (plural)
• is (singular)
• were (plural, past)
• have been (plural)

To see what works here, I need to figure out what the subject is in this clause.

Let's look carefully at this phrase:

• 'the shape of each statue's ears'

Now here's what we notice about the structure:

• 'The shape' is the main subject
  • NOT 'ears' – that word appears in the prepositional phrase 'of each statue's ears'
  • The prepositional phrase tells us WHICH shape we're talking about, but 'shape' is still the subject

• The phrase 'like the shape of each person's ears'
  • is just a comparison, set off by commas
  • This is telling us that statue ears are like human ears in this respect
  • But this phrase doesn't change what the subject is

So the subject is 'the shape' – that's singular.

The sentence is saying: each individual statue has ears with a unique shape, just like each individual person has ears with a unique shape.

Since 'the shape' is singular, we need a singular verb.

Looking at our choices:

• 'are' – plural, doesn't match
• 'is' – singular, MATCHES ✓
• 'were' – plural, doesn't match
• 'have been' – plural, doesn't match

So we need is.

GRAMMAR CONCEPT APPLIED

Subject-Verb Agreement with Intervening Phrases

When a subject and verb are separated by prepositional phrases or descriptive phrases set off by commas, the verb must still agree with the actual subject, not with nouns that appear in those intervening phrases.

The pattern:

• Subject + prepositional phrase (of/with/for + noun) + verb
• The subject and verb must agree
• Ignore the noun in the prepositional phrase

Example 1:

• The box of chocolates is on the table
• Subject: "box" (singular)
• Prepositional phrase: "of chocolates"
• Verb: "is" (singular) ✓
• NOT "are" even though "chocolates" is plural

Example 2:

• The students in the classroom are studying
• Subject: "students" (plural)
• Prepositional phrase: "in the classroom"
• Verb: "are" (plural) ✓

In our question:

• "The shape of each statue's ears" + comma phrase + "is unique"
• Subject: "the shape" (singular)
• Prepositional phrase: "of each statue's ears"
• Comma phrase: "like the shape of each person's ears"
• Verb needed: "is" (singular) ✓

The words "ears" appear multiple times, but they're never the subject - they're always inside prepositional phrases describing which shape we're talking about.