Question 203·Medium·Boundaries
During the filming of the _____ process that lasted nearly three years—researchers visited more than fifty remote islands.
Which choice completes the text so that it conforms to the conventions of Standard English?
For sentence-boundary and punctuation questions, first strip the sentence down to its core subject and verb to see what must stay together. Then identify whether any phrases are interruptions or extra information, and check that they are set off with matching punctuation on both sides. Remember that semicolons and colons can only follow a complete sentence, while dashes and commas can set off nonessential phrases; eliminate any choice that mislabels fragments as full sentences or mismatches punctuation around an interruption.
Hints
Find the main clause
Temporarily ignore the blank and the words after it. What are the subject and verb of the main clause in this sentence?
Look at the phrase around the blank
Focus on a process that lasted nearly three years. Is this phrase essential to the structure of the sentence, or is it extra information interrupting the main idea?
Notice the punctuation already given
There is already a punctuation mark after the words three years before researchers. How should the punctuation in the blank relate to that mark?
Think about what semicolons and colons require
Ask yourself: Does During the filming of the documentary form a complete sentence that could stand alone before a semicolon or colon?
Step-by-step Explanation
Understand the basic sentence structure
Strip away the extra description to see the core sentence:
- Core:
During the filming of the documentary ... researchers visited more than fifty remote islands.
Here, the main clause is researchers visited more than fifty remote islands, and During the filming of the documentary is just an introductory phrase leading into that clause.
Identify the interrupting phrase
Now look at the full version:
During the filming of the _____ process that lasted nearly three years—researchers visited more than fifty remote islands.
The words a process that lasted nearly three years are extra information describing the filming of the documentary. That makes this an interrupting (nonessential) phrase, which must be set off with matching punctuation marks on both sides.
You can already see one punctuation mark closing this interruption: the dash right after years before researchers.
Decide what kind of punctuation is needed before the interrupting phrase
Because there is already a dash after years, the punctuation in the blank must:
- Match that closing mark (the dash) to set off the interrupting phrase as a pair, and
- Not turn
During the filming of the documentaryinto a complete sentence, since it is only an introductory phrase and cannot stand alone.
Semicolons and colons both require a complete sentence (independent clause) before them, which During the filming of the documentary is not. A single comma would mismatch the dash already used at the end of the interruption.
Evaluate the choices and select the only one that fits
Check each option:
documentary; awould give...documentary; a process...but a semicolon must come after a complete sentence, andDuring the filming of the documentaryis not a complete sentence.documentary, awould give...documentary, a process...but the interruption would then start with a comma and end with a dash, which is inconsistent.documentary: awould give...documentary: a process...but a colon also requires a complete sentence before it, which we do not have.documentary—astarts the interruption with a dash, matching the dash afteryearsand correctly setting off the nonessential phrase.
Therefore, the correct answer is B) documentary—a.