Commas
Learn proper comma usage with dependent clauses, transitions, and essential/non-essential information.
4Dependent Clauses
Rule:
When a dependent clause begins a sentence, follow it with a comma. If it follows the main clause, omit the comma unless it adds non-restrictive information or clarifies meaning.
Key Points:
- Use a comma after an introductory clause.
- Omit the comma if the clause is essential (restrictive).
- Add the comma if the clause is non-restrictive or improves clarity.
Correct: If it rains, we'll stay inside.
Correct: We'll stay inside if it rains.
Correct: We'll stay inside, if it rains, to keep warm.
Incorrect: If it rains we'll stay inside. (missing comma)
Correct: We'll stay inside if it rains.
Correct: We'll stay inside, if it rains, to keep warm.
Incorrect: If it rains we'll stay inside. (missing comma)
Practice Questions
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5Transitions (Conjunctive Adverbs)
Rule:
Transitions like however, therefore, furthermore connect ideas and require specific punctuation.
Key Points:
- Use semicolon before and comma after when connecting sentences
- Common transitions: however, therefore, furthermore, nevertheless, consequently
- Choose transitions that match the logical relationship
Correct: The experiment failed; however, we learned valuable information.
Correct: The roads were icy; therefore, many accidents occurred.
Incorrect: The experiment failed, however, we learned valuable information.
Correct: The roads were icy; therefore, many accidents occurred.
Incorrect: The experiment failed, however, we learned valuable information.
Practice Questions
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6Non-Essential Information
Rule:
Non-essential information should be set off with matching punctuation: commas, dashes, or parentheses.
Key Points:
- Use two commas, two dashes, or two parentheses
- Never mix different types of punctuation
- The sentence should make sense without the non-essential information
Correct: Paris, which is in France, is beautiful.
Correct: My brother—who lives abroad—is visiting.
Incorrect: My brother, who lives abroad—is visiting. (mixed punctuation)
Correct: My brother—who lives abroad—is visiting.
Incorrect: My brother, who lives abroad—is visiting. (mixed punctuation)
Practice Questions
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7Essential vs. Non-Essential
Rule:
Essential information identifies which specific thing you're talking about. Non-essential information provides extra details.
Key Points:
- Essential information: no commas
- Non-essential information: use commas, dashes, or parentheses
- Ask: "Do I need this information to identify what I'm talking about?"
Essential: My friend Sarah is coming to dinner. (identifies which friend)
Non-essential: My sister, who is a doctor, lives in Boston. (extra information)
Context matters: The author Stephen King wrote many novels. (if context is clear)
Non-essential: My sister, who is a doctor, lives in Boston. (extra information)
Context matters: The author Stephen King wrote many novels. (if context is clear)
Practice Questions
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8Comma Rules
Rule:
Commas separate items in lists, coordinate adjectives, and set off introductory elements.
Key Points:
- Use commas to separate items in a series
- Use commas between coordinate adjectives
- Never separate subject and verb with a comma
- Use commas after introductory elements
Correct: I need to buy apples, bananas, and oranges.
Correct: The tall, dark stranger entered the room.
Incorrect: The cat, jumped over the fence. (separates subject and verb)
Correct: The tall, dark stranger entered the room.
Incorrect: The cat, jumped over the fence. (separates subject and verb)
Practice Questions
Score: 0 / 5