Compound Sentences
A compound sentence contains two or more independent clauses joined together.
Independent Clauses
An independent clause can stand alone as a complete sentence:
- I like coffee.
- She prefers tea.
Joining with Coordinating Conjunctions
Use FANBOYS to connect independent clauses:
| Letter | Conjunction | Meaning |
|---|---|---|
| F | for | because, reason |
| A | and | addition |
| N | nor | negative addition |
| B | but | contrast |
| O | or | alternative |
| Y | yet | contrast (surprising) |
| S | so | result |
Examples
For (reason):
- I’m tired, for I worked all night.
And (addition):
- I like coffee, and she likes tea.
Nor (negative addition):
- I don’t drink coffee, nor do I drink tea.
But (contrast):
- I like coffee, but she prefers tea.
Or (alternative):
- We can go to the cinema, or we can stay home.
Yet (surprising contrast):
- He is rich, yet he is unhappy.
So (result):
- It was raining, so we stayed inside.
Punctuation Rule
Comma before the conjunction when joining two independent clauses:
- I wanted to go, but it was too late. ✓
- I wanted to go but it was too late. ✗
No comma with compound elements (not full clauses):
- I like coffee and tea. ✓ (compound object)
- She sings and dances. ✓ (compound verb)
Joining with Semicolons
Use a semicolon between closely related independent clauses:
- I like coffee**;** she prefers tea.
- It was cold**;** we wore our coats.
With Conjunctive Adverbs
| Adverb | Meaning |
|---|---|
| however | but |
| therefore | so |
| moreover | and (emphasis) |
| nevertheless | but (despite) |
| consequently | as a result |
Pattern: clause**;** adverb**,** clause
- I was tired**;** however**,** I finished the work.
- She studied hard**;** therefore**,** she passed.
Common Mistakes
Run-on Sentences
Two clauses with no connection:
I like coffee she likes tea.✗- I like coffee**,** and she likes tea. ✓
- I like coffee**;** she likes tea. ✓
Comma Splices
Only a comma, no conjunction:
I like coffee, she likes tea.✗- I like coffee**,** but she likes tea. ✓
Coordinating conjunctions (FANBOYS: for, and, nor, but, or, yet, so) join two independent clauses. A comma before the conjunction is standard in American English and recommended in British English to avoid ambiguity.