Smaller than poppy seeds, tardigrades are tiny, but they are tough. These minuscule animals can survive for thirty years without...

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

Sentence 1:

• Smaller than poppy seeds,
• tardigrades are tiny,
• but they are tough.

Sentence 2:

• These minuscule animals can survive for thirty years without food or water,
• and [?] can withstand extreme temperatures as low as minus 328 degrees and as high as 304 degrees Fahrenheit.

Understanding the Meaning

The first sentence introduces us to tardigrades:

• 'Smaller than poppy seeds'
  • tells us just how tiny these creatures are
• 'tardigrades are tiny, but they are tough'
  • confirms their small size but emphasizes their toughness
  • Note: the sentence already uses 'they' to refer to tardigrades

Now the second sentence gives us specific examples of that toughness:

• 'These minuscule animals can survive for thirty years without food or water'
  • 'These minuscule animals' = tardigrades (another way of referring to them)
  • They can go 30 years without food or water!

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

• 'and ______ can withstand extreme temperatures as low as minus 328 degrees and as high as 304 degrees Fahrenheit'

Let's look at our choices:

• We're choosing between different pronouns: "that," "it," "they," or "he"
• This pronoun needs to refer back to what the sentence is about

What do we know so far?

• The subject of this sentence is 'these minuscule animals' - that's plural
• The sentence is listing two amazing abilities:
  • First: can survive for thirty years without food or water
  • Second: [blank] can withstand extreme temperatures
• The blank needs a pronoun that refers to 'these minuscule animals'

What do we notice?

• 'These minuscule animals' is plural (more than one animal)
• We need a plural pronoun to match this plural subject
• Looking at our choices, only 'they' is plural

So we need: they - it's the only plural pronoun that correctly refers back to 'these minuscule animals.'

The complete sentence tells us: These tiny but tough animals can survive extreme conditions in two ways - going without food/water for decades AND withstanding incredibly extreme temperatures (both super cold and super hot).

Grammar Concept Applied

Matching Pronouns to What They Refer To (Pronoun-Antecedent Agreement)

When you use a pronoun to refer back to a noun you mentioned earlier (called the antecedent in grammar terms), the pronoun must match that noun in number - if the noun is plural, the pronoun must be plural; if the noun is singular, the pronoun must be singular.

Pattern:

• Plural noun → Plural pronoun
  • "The students finished their homework" ✓
  • "The students finished his homework" ✗
• Singular noun → Singular pronoun
  • "The student finished his homework" ✓
  • "The student finished their homework" ✗ (in formal standard English)

In this question:

• Antecedent: "these minuscule animals" (plural)
• Pronoun needed: "they" (plural)
• "These minuscule animals can survive...and they can withstand..." ✓

Note: The first sentence already establishes this pattern: "tardigrades are tiny, but they are tough" - using the plural "they" to refer to the plural "tardigrades."