What is a run-on sentence?

• A. A sentence that joins two or more independent clauses without proper punctuation or conjunction.
• B. A sentence that uses only one independent clause.
• C. A sentence that has a dependent clause at the end.
• D. A sentence that ends with a period.

Answer: (A)

A run-on happens when two complete thoughts are joined together without the right punctuation or a linking word. An independent clause is a group of words with a subject and a verb that can stand alone as a sentence. So, when you glue two of these together without proper punctuation or a conjunction, you get a run-on, like “I went to the store I bought milk.”

You can fix it by separating the two thoughts with a period: “I went to the store. I bought milk.” or by using a semicolon: “I went to the store; I bought milk.” You can also join them with a comma and a coordinating conjunction (for, and, nor, but, or, yet, so): “I went to the store, and I bought milk.”

If a sentence has only one independent clause, it isn’t a run-on. If a sentence ends with a dependent clause, it’s a complex sentence, not a run-on. Ending with a period is simply the normal, finished sentence.