Compound Sentences
A compound sentence joins two or more independent ideas of equal importance. Mastering them lets you write more fluently and connect your thoughts clearly.
What is a compound sentence?
A compound sentence contains two or more independent clauses — clauses that could each stand alone as a complete sentence. They are joined by a coordinating conjunction, a semicolon, or a conjunctive adverb.
Method 1 — Coordinating conjunctions (FANBOYS)
The most common way to form a compound sentence is with a coordinating conjunction preceded by a comma.
| Conjunction | Meaning | Example |
|---|---|---|
| for | reason / cause | She left early, for she had a train to catch. |
| and | addition | He cooked dinner, and she washed the dishes. |
| nor | negative addition | He didn't call, nor did he send a message. |
| but | contrast | I wanted to go, but I was too tired. |
| or | alternative | You can stay, or you can leave. |
| yet | unexpected contrast | It was cold, yet the children played outside. |
| so | result | She missed the bus, so she called a taxi. |
I like tea, but my sister prefers coffee.
The alarm went off, yet nobody woke up.
We can walk to the station, or we can take a cab.
Method 2 — Semicolon
A semicolon (;) can join two closely related independent clauses without any conjunction. The ideas should be closely linked in meaning.
The sun set; the stars appeared.
She loves hiking; he prefers swimming.
The report was finished; it was sent immediately.
Method 3 — Conjunctive adverbs
Conjunctive adverbs join clauses with a semicolon before and a comma after: ; however, ; therefore, ; moreover, ; nevertheless,
He worked all night; however, he still missed the deadline.
The price was high; nevertheless, they bought the car.
She trained for months; therefore, she felt confident.
Compound vs. simple sentences
| Type | Structure | Example |
|---|---|---|
| Simple | One independent clause | She went to the shop. |
| Compound | Two+ independent clauses | She went to the shop, and she bought some milk. |
Comma splice: Do not join two independent clauses with only a comma — She was tired, she went to bed is incorrect. Use a conjunction (she was tired, so she went to bed) or a semicolon.
Tip: Both clauses in a compound sentence must be able to stand alone. If one part cannot stand alone, the sentence is not compound — it may be complex.