Consider the mechanics of the pinhole camera: light passes through a small hole, resulting in a focused projected image. A...

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

• Consider the mechanics of the pinhole camera:
  • light passes through a small hole,
    • resulting in a focused projected image.
• A ray diagram
  • reveals
    • how this works [?]
      • the hole's small size restricts light to a single ray,
      • all light passing through the hole can only arrive
        • at a single destination,
          • eliminating diffraction and
          • ensuring a clear image.

Understanding the Meaning

The first sentence gives us the basic setup:

• Consider how a pinhole camera works
  • Light passes through a small hole
  • This results in a focused, projected image

The second sentence begins:

• 'A ray diagram reveals how this works...'
  • A ray diagram (a physics diagram showing light paths) will show us the mechanism

This is where we have the blank.

Let's look at the choices:

• A: works because
• B: works. Because
• C: works, it's because
• D: works: it's because

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

The rest tells us:

• 'the hole's small size restricts light to a single ray'
  • The key is that the hole is SMALL
  • This smallness limits the light to just one ray
• 'all light passing through the hole can only arrive at a single destination'
  • Because it's restricted to a single ray
  • That light can only go to one specific spot
• 'eliminating diffraction and ensuring a clear image'
  • This is what produces the clear image we want

Now, what do we notice about the structure here?

• 'A ray diagram reveals how this works'
  • This is a complete thought that could stand as its own sentence
• 'Because the hole's small size restricts light to a single ray, all light passing through the hole can only arrive at a single destination'
  • 'Because the hole's small size restricts light to a single ray' is giving us a reason (dependent clause)
  • 'all light passing through the hole can only arrive at a single destination' is a complete statement (independent clause)
  • Together: dependent clause + independent clause = complete sentence

So we have two complete sentences here!

• The first ends with "works"
• The second begins with "Because" and has proper structure (dependent clause followed by independent clause)

The correct answer is B: works. Because

We need a period to separate these two complete sentences. Even though the second sentence starts with "Because," it's grammatically correct because the dependent clause ("Because the hole's small size...") is followed by a main clause ("all light passing through...").

Grammar Concept Applied

Understanding Sentence Boundaries and Starting Sentences with "Because"

Two important principles work together here:

Principle 1: Complete thoughts need proper separation

• When you have two complete thoughts (called independent clauses in grammar terms), you need to separate them with:
  • A period (creating two sentences)
  • A semicolon
  • A comma + coordinating conjunction (and, but, or, so, etc.)
• You CANNOT join them with just a comma (this creates a comma splice)

Principle 2: Sentences CAN start with "Because" when structured properly

Many students learn "don't start sentences with because," but this isn't always true! It's fine when:

• The "because" clause is followed by a main clause
• Structure: Because [reason], [main statement].

Example:

• Incorrect fragment: "Because it was raining."
  • This is only a dependent clause with no main statement
• Correct sentence: "Because it was raining, we stayed inside."
  • Dependent clause: "Because it was raining"
  • Main clause: "we stayed inside"
  • Together they form a complete sentence

In this question:

• First sentence: "A ray diagram reveals how this works."
  • Complete thought - gets a period
• Second sentence: "Because the hole's small size restricts light to a single ray, all light passing through the hole can only arrive at a single destination, eliminating diffraction and ensuring a clear image."
  • Starts with "Because" BUT has proper structure
  • Dependent clause + independent clause = complete sentence