There are two kinds of run-on sentences. The first is when a writer does not utilize a punctuation mark or a coordinating conjunction between independent clauses. The second is referred to as a "comma splice," and it happens when two or more independent sentences are connected by a comma but no coordinating conjunction. Examples of these types of run-on sentences are: "Mike went to the store, bought some milk, and returned home. Here is an example of a comma splice: "Mike went to the store, bought milk, and returned home." This sentence has a comma splice because there is no conjunctive word (and, or, but) between the two sentences. Comma splices can be difficult to spot unless you are looking for them, so be sure to read your work carefully before you submit it. A run-on sentence may not necessarily contain a comma; rather, it is defined as having incomplete ideas or sentences separated only by white space. For example, this sentence contains two runs-on sentences: "The dog ran up to Mike and wagged its tail." Here, "up" and "tail" are modifiers that describe the action of running, but they don't complete any full thoughts on their own. White space is used instead to indicate where each idea should end. A comma splice also uses white space to show separation between sentences.