Question 136·Easy·Boundaries
The new community center offers _____ all of which are accessible to local residents: a gymnasium, a computer lab, and a rooftop garden.
Which choice completes the text so that it conforms to the conventions of Standard English?
For boundaries questions, identify what grammatical structure begins immediately after the blank. If the next words introduce a nonrestrictive clause (often signaled by "which" or "all of which"), you need a comma to set it off; reserve semicolons for joining two independent clauses and colons for introducing lists or explanations after a complete clause.
Hints
Look at the words right after the blank
The words right after the blank are "all of which...". What kind of clause does that usually introduce?
Recall the rule for nonrestrictive clauses
Nonrestrictive clauses (extra information) are set off with commas.
Check semicolon vs. comma
Does what follows the blank form a complete sentence? If not, a semicolon won’t work.
Step-by-step Explanation
Identify the structure around the blank
Read the sentence with the blank:
"The new community center offers _____ all of which are accessible to local residents: a gymnasium, a computer lab, and a rooftop garden."
Recognize the nonrestrictive clause
The phrase "all of which are accessible to local residents" is a nonrestrictive clause describing "amenities." Nonrestrictive clauses must be separated from the main clause with a comma.
Eliminate punctuation that can’t precede the clause
- A colon (:) should not be used here because what immediately follows is not a list; it’s a clause (and it would also lead to a second colon later in the sentence).
- A semicolon (;) cannot be used because it must be followed by an independent clause, and "all of which are accessible to local residents" is not an independent clause.
- No punctuation incorrectly runs the noun into the nonrestrictive clause.
Confirm the best choice in the full sentence
With the comma, the sentence correctly sets off the nonrestrictive clause and keeps the later colon to introduce the list of amenities.
Therefore, the correct choice is amenities,.