Common Core L.6.2.A states students should use punctuation (commas, parentheses, dashes) to set off nonrestrictive/parenthetical elements. So, is there a difference between the three? Some resources say no. Others say yes. This post will list the rules pointing out the differences in the three, so you can decide.
Nonrestrictive vs. Restrictive Elements
First, you need to understand the meanings of nonrestrictive and restrictive elements.
Nonrestrictive elements are groups of words that can be removed from the sentence without changing its meaning. The sentence would still make sense without the parenthetical element. Nonrestrictive elements add extra information that is nonessential.
Restrictive elements are necessary to retain the meaning of the sentence.
The two largest land animals on the earth – the African elephant and the giraffe – are herbivores.
The appositive (the African elephant and the giraffe) is a nonrestrictive element. You can remove it from the sentence, and the sentence makes sense. The phrase adds extra information that is nonessential to the meaning of the sentence. — The two largest land animals on the earth are herbivores.
All students who do their work should pass easily.
If you remove the clause – who do their work – from this sentence it changes the meaning. The clause is important because not all students will pass, only those who do their work will pass. Because of this, the clause is restrictive.
Parenthetical Elements – Important Rule
Parentheses, commas, or dashes separate the rest of the sentence from the parenthetical element. YOU MUST use the same punctuation on each side of the parenthetical element. You will not mix dashes with commas or parenthesize with dashes. SO, if you use commas, use 2, and so on.
Eight Types of Parenthetical Elements
direct address – the name of the person who is being directly spoken to
- Yes, George, you may go to the movies on Saturday.
appositive – nouns or phrases that rename preceding nouns or phrases
- Our mayor, Mike Taylor, gave a speech.
- The beautiful flowers, red and yellow roses, smell sweet.
- Sally Smith, the best ballerina in the show, shone as the star of the evening.
participial phrases – verb-based phrases that describe (modify) nouns or pronouns
- Eaten by mosquitoes, we wished we had not gone camping near the swamp.
- Quickly checking over his answers, Bill handed in his assignment.
- Removing his glasses, Clark Kent became Superman.
clarification – words that make an idea, statement, etc. clear or intelligible
- The town where I live (Blowing Rock) is a tourist destination in the mountains of North Carolina.
i.e. and e.g. – phrases beginning with e.g. (for example) or i.e. (in other words)
- I like chocolate, i.e., the creamy sweetness that melts in your mouth.
- I like chocolate, e.g., Swiss milk chocolate, white chocolate, sweet chocolate, and even chocolate milk.
explanation – something (such as a statement of fact) that explains something
- The school year (this year that’s August 3 – May 25) includes 180 school days.
interjection – word, phrase, or sound used to convey an emotion such as surprise, excitement, happiness, or anger
- We’re having a snow day, yippee!
a joke or play on words
- Energizer Bunny arrested – charged with battery.
- The knight (Sir Render) was afraid to fight.
- The sleeping bull (not bull-dozer) woke up and charged.
When to Use Commas, Parentheses, and Dashes
Add Comment with Commas
Use commas before and after clauses that are closely related (description, clarification, or detail) to the main idea.
De-emphasize Comments with Parentheses
Parentheses are used to enclose comments that turn away from the main idea of the sentence. The clause could be an afterthought, side comment, or explain circumstances.
Emphasize Comments with Dashes
Dashes are used to separate a comment that is loosely related to the main idea. They are used when interrupting, contrasting, or for an afterthought. Dashes should be used sparingly.