You can correct run-ons by adding a period to make two separate sentences. After adding the period, capitalize the letter that begins the new sentence. Reread your two sentences to make sure they each contain a subject, a verb, and a complete thought.

A semicolon (;) can be used instead of a period to join two closely related sentences. Do not capitalize the word that follows a semicolon unless it is the name of a specific person, place, or thing that is usually capitalized — for example, Mary, New York, or the Eiffel Tower.

NOTE: The semicolon may be followed by a conjunctive adverb — such as however, indeed, instead, moreover, nevertheless, and similarly — and a comma.