Question 123·Hard·Boundaries
Researchers at the Marine Institute have deployed a network of acoustic sensors in Deep _____ quiet inlet north of the main harbor—to determine how boat traffic affects the communication patterns of local dolphin pods.
Which choice completes the text so that it conforms to the conventions of Standard English?
For boundaries questions, first remove the words between the blank and the later punctuation to see if the main sentence is complete. If the removed words are extra (nonessential) information, they must be set off with matching punctuation on both sides (commas with commas, dashes with dashes, etc.). Eliminate semicolons and colons unless what follows clearly forms (or is introduced by) a complete independent clause.
Hints
Find the core sentence
Try reading the sentence while skipping the words between the blank and the existing dash. Does the remaining sentence still form a complete thought?
Identify the role of the middle phrase
Decide whether the words after the blank are a complete sentence or just extra information describing “Deep Cove”.
Match the punctuation
Look at the punctuation mark already used after the descriptive phrase. What punctuation at the blank would create a matching pair?
Step-by-step Explanation
Find the core sentence
Read the sentence without the interrupting description:
“Researchers at the Marine Institute have deployed a network of acoustic sensors in Deep Cove … to determine how boat traffic affects the communication patterns of local dolphin pods.”
The sentence is complete without the middle phrase, so the words between the blank and the existing dash are nonessential information (an appositive).
Use matching punctuation for nonessential information
Nonessential information that interrupts a sentence should be set off with a matching pair of punctuation marks:
- commas:
Deep Cove, a quiet inlet, ... - dashes:
Deep Cove—a quiet inlet—...
Since there is already a dash after the appositive phrase, the punctuation before it should also be a dash.
Test the choices
Cove, thewould create mismatched punctuation around the same nonessential phrase (comma to open, dash to close).Cove; theis incorrect because a semicolon joins two independent clauses, and what follows is not an independent clause.Cove: theis incorrect because a colon must follow a complete clause and is not used as one half of a paired interruption.Cove—thecorrectly opens a dash-set appositive that is closed by the existing dash.
Therefore, the correct answer is Cove—the.