College Composition / Unit 7 CMP 0156 short lesson, about 20 seconds
Nonessential Information
Captions available
The idea
Nonessential information adds detail but is not needed to identify what the sentence means, and it is set off with commas.
In practice
"The department chair, who teaches welding, wrote the report." There is one chair, so the clause only adds detail.
Where people slip
Nonessential information needs commas on both sides unless it ends the sentence.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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