What is a combination of two or more complete sentences without proper punctuation called?

A combination of two or more complete sentences without proper punctuation is referred to as a run-on sentence. This occurs when independent clauses, which can stand alone as separate sentences, are joined together improperly. Run-on sentences often lack the necessary punctuation or conjunctions needed to separate the ideas clearly. For example, combining "It is raining" and "I will bring an umbrella" without a conjunction or punctuation creates confusion because it makes the sentence hard to read and understand.

In contrast, a compound sentence correctly combines two independent clauses with a coordinating conjunction, while a complex sentence consists of an independent clause and at least one dependent clause, demonstrating a different structure entirely. A complete sentence represents a single thought with both a subject and a predicate, standing independently. Thus, recognizing run-on sentences is essential for effective writing and clarity in communication.