compound sentence

A compound sentence is a sentence made of two or more independent clauses, usually joined by a conjunction. A compound sentence has no dependent clauses.

In grammar, a clause is a group of words that contains a subject and a predicate. The subject is the word that indicates what a sentence is about or who or what is performing an action. A subject can be a noun (car, Tom), a noun phrase (short book, green apples), or a noun substitute (you, they). The predicate is a word that indicates what the subject is doing. A predicate is a verb (runs, is) and the words that govern or modify it (fast, hungry).

An independent clause contains a complete thought and can be used by itself as a sentence, as in It is time for lunch. A dependent clause does not contain a complete thought and can’t be used by itself. It depends on another clause to make sense, as in When the clock strikes noon.

A compound sentence has only independent clauses, as in Selena studied for hours, but she failed the exam. Selena studied for hours is a complete thought that grammatically can stand alone as a sentence. She failed the exam is also a complete thought that can stand alone as a sentence. But is a coordinating conjunction that joins the sentences together. Coordinating conjunctions join two equal (coordinate) parts.

A compound sentence can have any number of independent clauses but cannot have any dependent clauses, as in I like Sarah, and Sarah likes Jessica, but Jessica doesn’t like me.

The first records of the phrase compound sentence come from around 1765. It combines the word compound, meaning “composed of two or more parts,” and sentence, meaning “a grammatical unit of words that expresses an independent idea.” A compound sentence is composed of two or more independent clauses.

Compound sentences help us share two or more main ideas (independent clauses) in one sentence. Because there are no dependent clauses in a compound sentence, we aren’t usually sharing further, more complex information about either main idea, as in The wind howled and the rain poured.

The independent clauses in a compound sentence can be joined by a coordinating conjunction, such as and, but, or or. The conjunction often follows a comma, as in Juan studied for the exam, but Shane did not. When you have more than two independent clauses, use commas between the clauses and a comma and a coordinating conjunction between the last two clauses, as in Yvette likes chocolate ice cream, Luis likes vanilla, and Sally likes strawberry.

Understanding compound sentences will help you understand the relationship between the ideas in the sentence and help you understand similar sentence structures, such as complex sentences and compound-complex sentences.

You can also join two independent clauses with just a semicolon, as in Juan studied for the exam; Shane did not.

This graphic defines a complex sentence and gives two examples.

We use compound sentences all of the time in English.

All of those three things have their uses. I don't remove them all. But as for the semi-colon, I think that my mind works in compound sentences so my writing often comes out that way initially. It's easy enough to rectify though, and a well-placed semi-colon is a wonderful thing.

— Michael Burnett: Memento Mori. (@MementoMoriMB) March 15, 2021

I like compound sentences because it's like two independent clauses decided to get married.

— Quirky Cat (@RealQuirkyCat) March 6, 2015

• sentence
• clause
• independent clause
• dependent clause
• subject
• predicate
• coordinating conjunction
• simple sentence
• complex sentence
• compound-complex sentence

Is the following sentence an example of a compound sentence?

I love dogs, but I am afraid of cats.