Commas Around a Nonessential Phrase
Question
My oldest brother who lives in Toronto is flying down for the holidays.
Answer choices
- brother who lives in Toronto,
- NO CHANGE
- brother, who lives in Toronto
- brother, who lives in Toronto,
D Correct answer: D) brother, who lives in Toronto,
Because there is only one "oldest brother," the phrase "who lives in Toronto" is extra information — true, but not needed to identify which brother. Nonessential information must be set off by paired commas, one before and one after.
The other options either introduce a grammatical error or change the intended meaning. The ACT consistently rewards the most concise, grammatically correct option.
Read the sentence with each option substituted in. The version that preserves meaning while obeying the underlying rule is the correct answer; on the ACT, that is almost always the shortest option that still works.
The underlying rule
A nonessential modifier — one whose removal would not change the meaning of the main clause — must be set off with commas on both sides. Here, the speaker has only one "oldest brother," so the location detail is nonessential.
Why each wrong answer is wrong
- A) brother who lives in Toronto,: This option either omits a required comma or uses only one of the pair that a nonessential modifier requires.
- B) NO CHANGE: This option either omits a required comma or uses only one of the pair that a nonessential modifier requires.
- C) brother, who lives in Toronto: This option either omits a required comma or uses only one of the pair that a nonessential modifier requires.
Study tip
Test by removing the phrase. If the sentence still makes sense and identifies the same noun, the phrase is nonessential and needs commas around it. If removing it changes which noun is being identified, it is essential and takes no commas.
More Hard Punctuation
- Comma Before a Coordinating ConjunctionThe hike was long and exhausting, but the view from the summit was worth every step
- Semicolons in a Complex ListThe conference featured speakers from Austin, Texas; Portland, Oregon, and Madison,
- Apostrophe with a Plural PossessiveThe students' projects were displayed in the auditorium for the science fair.
- Colon Before a ListThe recipe called for three simple ingredients, flour, butter, and salt.
- Comma Before a Coordinating ConjunctionThe hike was long and exhausting, but the view from the summit was worth every step