How is a compound sentence defined?

A compound sentence is defined as a sentence that contains two or more independent clauses, which are joined by a coordinating conjunction such as "and," "but," "or," "nor," "for," "so," or "yet." Each independent clause must be able to stand alone as a complete sentence, possessing its own subject and verb. This structure allows for the combination of related ideas, giving the sentence more complexity and depth in conveying relationships between thoughts.

For instance, in the compound sentence “I wanted to go for a walk, but it started to rain,” both independent clauses can function independently but are connected to express a relationship between the speaker's desire and the unexpected circumstance.

The other definitions do not accurately describe a compound sentence. A sentence that expresses a single idea refers to a simple sentence, which consists of only one independent clause. A sentence with one independent clause and one dependent clause defines a complex sentence, while a sentence that contains only one clause refers to either a simple or a compound-complex sentence. These distinctions highlight the uniqueness of the compound sentence structure.