📚 What is a Comma?
A comma (,) is a punctuation mark that indicates a pause in a sentence. It helps separate ideas, items, and clauses to make writing clearer and easier to read.
🎯 When to Use Commas
1. Items in a List (Series)
Use commas to separate three or more items in a list
I bought apples, oranges, and bananas.
She is smart, kind, and funny.
We need to pack clothes, food, and water.
💡 Oxford Comma:
The comma before "and" in a list is called the Oxford comma. It's optional but often helpful for clarity.
2. After Introductory Words or Phrases
Use a comma after words or phrases that come before the main sentence
Yes, I agree with you.
However, we need more time.
After school, I play soccer.
Running quickly, she caught the bus.
In the morning, I always eat breakfast.
3. Compound Sentences (FANBOYS)
Use a comma before coordinating conjunctions (for, and, nor, but, or, yet, so) when joining two complete sentences
I love reading, and my sister loves writing.
We wanted to go swimming, but it was too cold.
You can have cake, or you can have ice cream.
She studied hard, so she passed the test.
💡 Remember:
Only use a comma if BOTH sides of the conjunction are complete sentences.
✓ I like apples and oranges. (no comma - not two complete sentences)
4. Dependent Clauses at the Beginning
Use a comma when a dependent clause comes before an independent clause
Because it was raining, we stayed inside.
When I finish my homework, I can watch TV.
Although she was tired, she kept studying.
If you need help, please ask.
No comma when the independent clause comes first: "We stayed inside because it was raining."
5. Direct Address
Use commas to set off the name of someone you're speaking to directly
Sarah, please come here.
Thank you, Mr. Johnson, for your help.
I think, my friend, that you're right.
6. Dates and Addresses
Dates:
My birthday is July 15, 2010.
On Monday, June 5, we went to the park.
Addresses:
I live at 123 Main Street, Springfield, Illinois.
She moved to Portland, Oregon.
7. Interrupting Phrases
Use commas to set off words or phrases that interrupt the flow of the sentence
My teacher, Mrs. Smith, is very kind.
The book, as you know, is very popular.
I believe, however, that we can succeed.
8. Adjectives in a Row
Use commas between coordinate adjectives (adjectives that equally modify a noun)
She's a smart, talented, hardworking student.
The long, winding, narrow road led home.
💡 Test:
If you can put "and" between the adjectives and it sounds right, use a comma.
✓ "smart and talented" ✓ = smart, talented
✗ "big and red balloon" doesn't need comma before "balloon"
✏️ Practice Exercise
Add commas where needed. Click to reveal!
1. I need to buy eggs milk bread and butter.
I need to buy eggs, milk, bread, and butter.
Items in a list
2. When you're ready we can leave.
When you're ready, we can leave.
Dependent clause at the beginning
3. I wanted to go to the park but it started raining.
I wanted to go to the park, but it started raining.
Compound sentence with FANBOYS
4. Sarah can you help me with my homework?
Sarah, can you help me with my homework?
Direct address
5. My birthday is on March 15 2012.
My birthday is on March 15, 2012.
Date format
6. The tall dark mysterious stranger entered the room.
The tall, dark, mysterious stranger entered the room.
Coordinate adjectives
⚠️ Common Mistakes
❌ Comma Splice
Don't connect two complete sentences with just a comma
I love reading, my sister loves writing.
✓ I love reading, and my sister loves writing.
✓ I love reading. My sister loves writing.
❌ Unnecessary Commas
I like, apples and oranges.
✓ I like apples and oranges.
❌ Missing Comma in Compound Sentence
She studied hard so she passed the test.
✓ She studied hard, so she passed the test.
🎯 Key Takeaways
- Use commas to separate items in a list (3 or more items)
- Use a comma after introductory words/phrases
- Use a comma before FANBOYS in compound sentences
- Use a comma after a dependent clause at the beginning
- Use commas for direct address (names of people you're talking to)
- Use commas in dates and addresses
- Don't use commas to join two complete sentences without a conjunction (comma splice)