Rachel Carson's 1962 book Silent Spring meticulously documented the environmental damage caused by synthetic pesticides. The chemical industry launche...

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

• Rachel Carson's 1962 book Silent Spring
  • meticulously documented
  • the environmental damage
  • caused by synthetic pesticides
• The chemical industry
  • launched aggressive campaigns
  • to discredit her findings [?] however [?]
• her scientific evidence
  • proved too compelling
• and
• the book
  • catalyzed the modern environmental movement

Understanding the Meaning

Let's start with the first sentence to get context:

• 'Rachel Carson's 1962 book Silent Spring meticulously documented the environmental damage caused by synthetic pesticides.'
  • This tells us Carson wrote a book that carefully showed how synthetic pesticides harmed the environment.

Now the second sentence:

• 'The chemical industry launched aggressive campaigns to discredit her findings'
  • The chemical industry tried hard to make people not believe Carson's research.

This is where we have the blank with 'however' - let's look at the choices:

• A: findings, however
• B: findings however,
• C: findings, however,
• D: findings; however,

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

• 'her scientific evidence proved too compelling'
  • Carson's evidence was so strong and convincing that it couldn't be dismissed

• 'and the book catalyzed the modern environmental movement'
  • The book sparked the beginning of the modern environmental movement

So the complete picture is:

• The chemical industry tried to discredit Carson's findings,
• BUT her evidence was too strong,
• AND her book ended up launching the environmental movement.

What do we notice about the structure here?

• Look at what comes before 'however':
  • 'The chemical industry launched aggressive campaigns to discredit her findings'
  • This is a complete thought - it has a subject (the chemical industry), a verb (launched), and expresses a complete idea that could stand alone as a sentence.

• Look at what comes after 'however':
  • 'her scientific evidence proved too compelling, and the book catalyzed the modern environmental movement'
  • This is also a complete thought - it has its own subject (her scientific evidence), verb (proved), and expresses a complete idea that could stand alone.

• 'However' is showing a contrast between these two complete thoughts:
  • The industry tried to discredit her...
  • BUT her evidence was too strong.

When we have two complete thoughts being connected with a contrasting word like 'however,' we need:

• Strong punctuation before 'however' (a semicolon) to properly separate the two complete thoughts
  • A comma alone would be too weak - that would create what's called a comma splice
• A comma after 'however' to set off this transitional word

So we need findings; however, - that's Choice D.

Grammar Concept Applied

Connecting Two Complete Thoughts with Transitional Words

When you want to connect two complete thoughts (each with its own subject and verb, expressing complete ideas) using a transitional word like 'however,' 'therefore,' 'moreover,' or 'nevertheless,' you need:

1. A semicolon before the transitional word (to properly separate the two complete thoughts)
2. A comma after the transitional word (to set off the transition)

The pattern:

• Complete thought + ; transitional word, + complete thought

Examples:

• The experiment failed repeatedly; however, the team continued their research.
  • First complete thought: 'The experiment failed repeatedly'
  • Second complete thought: 'the team continued their research'
  • Connected with: ; however,

• The data supported the hypothesis; therefore, the study was published.
  • First complete thought: 'The data supported the hypothesis'
  • Second complete thought: 'the study was published'
  • Connected with: ; therefore,

In our question:

• The chemical industry launched aggressive campaigns to discredit her findings; however, her scientific evidence proved too compelling, and the book catalyzed the modern environmental movement.

Why not just a comma? Using only a comma to join two complete thoughts creates a comma splice (called a run-on sentence in grammar terms), which is one of the most common punctuation errors. The semicolon provides the necessary separation between the two complete ideas while showing they're related.