Want to make your writing flow and connect ideas like a pro? Compound sentences are the answer. They let you combine two big thoughts into one sentence, making your point clearer and more interesting—whether you’re saying what happened next or why things didn’t go as planned.
This guide explains what compound sentences are, how to build them, and gives tons of examples to help you use them confidently.
What Is a Compound Sentence?
A compound sentence consists of two or more independent clauses—complete thoughts that can stand alone—connected by a coordinating conjunction (for, and, nor, but, or, yet, so) or a semicolon. Each clause has its own subject and verb, and the conjunction or punctuation shows how the ideas relate, whether they’re adding, contrasting, or showing cause and effect.
For example:
“I wanted to go hiking, but it started raining.”
Here, “I wanted to go hiking” and “it started raining” are independent clauses, linked by but to show contrast.
Unlike simple sentences (one clause) or complex sentences (with dependent clauses), compound sentences balance equal ideas, making them perfect for expressing related thoughts without subordination.
Structure of a Compound Sentence
A compound sentence follows this basic pattern:
[Independent Clause] + [Conjunction or Semicolon] + [Independent Clause].
Key components:
- Independent Clauses: Each must be a full sentence with a subject and predicate. For example, “She smiled” and “he waved” can stand alone.
- Connectors:
- Coordinating Conjunctions: For, and, nor, but, or, yet, so (FANBOYS). A comma usually comes before the conjunction.
- Semicolon: Used when clauses are closely related, with no conjunction (e.g., “I ran; she walked.”).
- Conjunctive Adverbs: Words like however, therefore, or meanwhile can link clauses with a semicolon and comma (e.g., “I was tired; however, I kept going.”).
You can have more than two clauses, but two is the minimum:
“I studied, and I ate, but I skipped the party.”
Examples of Compound Sentences
Here are examples showcasing different relationships, using FANBOYS, semicolons, and conjunctive adverbs:
- Addition (And):
- “The sun shone brightly, and the birds sang loudly.” (Two related actions.)
- “She finished her book, and she started a new one.” (Sequential ideas.)
- Contrast (But, Yet):
- “I wanted coffee, but the shop was closed.” (Opposing ideas.)
- “He was exhausted, yet he stayed up late.” (Surprising contrast.)
- Choice (Or):
- “We can watch a movie, or we can play games.” (Alternatives.)
- “You can call me, or you can text me later.” (Options.)
- Cause/Result (For, So):
- “The storm hit, for the skies had darkened.” (Reason, formal.)
- “I forgot my lines, so I improvised on stage.” (Outcome.)
- Negative Choice (Nor):
- “She didn’t answer, nor did she call back.” (Both negatives, with inversion.)
- “I don’t like crowds, nor do I enjoy loud music.” (Paired exclusions.)
- Semicolon:
- “The hike was tough; the view was worth it.” (Closely related ideas.)
- “He left early; she stayed behind.” (Simple contrast.)
- Conjunctive Adverb:
- “I missed the bus; therefore, I was late.” (Cause and effect.)
- “She studied hard; however, she didn’t pass.” (Unexpected result.)
Why Use Compound Sentences?
Compound sentences elevate your writing by:
- Connecting Ideas: They show how thoughts relate—whether they build on each other, clash, or offer choices.
- Improving Flow: They avoid the choppiness of short, simple sentences. Compare: “I was hungry. I ate.” vs. “I was hungry, so I ate.”
- Adding Variety: Mixing compound sentences with simple or complex ones keeps readers engaged.
- Clarifying Relationships: They make it clear whether you’re adding (and), contrasting (but), or explaining (so).
For example:
Instead of: “The party was fun. I left early.”
Try: “The party was fun, but I left early.”
It ties the ideas together with context.
Punctuation and Grammar Rules
To get compound sentences right, follow these:
- Comma Before Conjunction: When joining two independent clauses with FANBOYS, place a comma before the conjunction:
- Right: “I ran, and I won.”
- Wrong: “I ran and I won.” (Missing comma.)
- Exception: Very short clauses can skip the comma, like “I laughed and she smiled,” but it’s safer to include it.
- Semicolon Without Conjunction: Use a semicolon for closely related clauses:
- Right: “I cooked; she cleaned.”
- Wrong: “I cooked, she cleaned.” (Needs a conjunction or semicolon.)
- Conjunctive Adverbs: Pair with a semicolon and a comma:
- Right: “I was sick; however, I went to work.”
- Wrong: “I was sick, however I went to work.” (Needs semicolon.)
- Avoid Run-Ons: Don’t just mash clauses together:
- Wrong: “I called her she didn’t answer.”
- Fix: “I called her, but she didn’t answer.” or “I called her; she didn’t answer.”
- Check Independence: Both clauses must stand alone. “I left, and running” is wrong—“running” isn’t a clause. Fix to “I left, and I ran.”
Common Uses in Writing
Compound sentences shine in different contexts:
- Narrative: “The moon rose, and the night felt magical.” (Sets a scene.)
- Persuasive: “We must act now, or we’ll lose our chance.” (Urges action.)
- Descriptive: “The beach was stunning, yet the water was cold.” (Balances impressions.)
- Explanatory: “I was delayed, for the train broke down.” (Gives context, though formal.)
Tips for Writing Compound Sentences
- Pick the Right Conjunction
Match the relationship: but for contrast, so for results. “I was tired, or I slept” doesn’t fit—try so. - Keep Clauses Balanced
Both clauses should feel equal in weight. “I ate dinner, and the sun set” works if related, but it might feel off otherwise. - Vary Connectors
Don’t overuse and. Try but, or, yet, or a semicolon for variety. - Test the Split
Split the sentence to check if both clauses stand alone: “I tried, but I failed” becomes “I tried.” and “I failed.”—both work. - Mind Formality
For and nor sound formal. In casual writing, use because or rephrase nor (e.g., “I didn’t call or text” instead of “nor texted”).
Common Mistakes to Avoid
- No Comma: “She sang and he danced” needs a comma if clauses are full: “She sang, and he danced.”
- Run-On: “I left it was late” needs fixing: “I left, for it was late.”
- Wrong Connector: “I was happy, but I won” implies contrast—use and or so.
- Dependent Clause Slip: “I laughed, and feeling great” fails—“feeling great” isn’t independent. Fix to “I laughed, and I felt great.”
- Overloading: “I ran, and I ate, and I slept” can feel repetitive—cap at two or three clauses.
Practice Examples
Try spotting or fixing these:
- “I was late so I ran.” (Needs a comma: “I was late, so I ran.”)
- “She called and he picks up.” (Fix: “She called, and he picked up.”)
- “I stayed; the rain fell.” (Correct—semicolon works for related ideas.)
- “He tried, or he succeeded.” (Wrong—or implies choice, not result. Try “He tried, and he succeeded.”)
Final Thoughts
Compound sentences are your go-to for linking equal ideas with flair, whether you’re adding (and), contrasting (but), or showing results (so). With examples like “I dreamed big, yet I stayed grounded,” you can see how they bring balance and rhythm. Keep FANBOYS or a semicolon in your toolkit, practice joining clauses, and watch your writing flow. What two ideas can you combine today to make your next sentence pop?