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Recipe

Find a run-on and name its degree

Use when: a sentence feels long or breathless and you suspect two complete sentences are jammed together

Goal: the exact seam between two independent clauses, and a label for what sits there -- nothing (first degree), a FANBOYS word with no comma (second degree), or a legal join (not a run-on at all)

Taught in Run-Ons: First and Second Degree · a later section extends this recipe with more cases

Quick recipe

  1. Find every subject-verb pair
  2. Test each stretch on its own
  3. Look at the seam and name the degree
  1. 1

    Mark each subject and its verb. One pair means one clause, and a single clause can't be a run-on.

    Why: a run-on needs two independent clauses, so counting subject-verb pairs is the fastest way to rule one out.

  2. 2

    Split the sentence where the second pair's subject begins, and read each half as if it ended with a period.

    Example

    The oven timer beeped the cookies were done. Pairs: timer beeped, cookies were. Split before the cookies: The oven timer beeped. The cookies were done. Both stand alone.

    • both halves stand alone as sentences — keep going; you may have a run-on.
    • one half can't stand alone (it has no subject of its own, or a word like because holds it open) — not a run-on. A shared subject with two verbs is one clause (She grabbed her keys and ran out the door).

    Why: the second half must have its own subject. Without one, the "second clause" is just a second verb for the first subject, and no comma belongs there.

  3. 3

    Look at what sits between the two halves.

    Example

    The oven timer beeped the cookies were done. Nothing between beeped and the: first degree. My brother likes hiking but I prefer the beach. But with no comma before it: second degree.

    • nothing at all — a first-degree run-on (a fused sentence).
    • a FANBOYS word (for, and, nor, but, or, yet, so) with no comma before it — a second-degree run-on.
    • a comma plus a FANBOYS word, a semicolon, or a period — correctly joined; not a run-on.
    • Not yet: it is a run-on, and you need to repair it — covered in Fix It Three Ways

    Why: the two degrees need different amounts of repair. A second-degree run-on already has its joining word, so one comma fixes it.

Common mistakes

  • Calling a long sentence a run-on because it is long. Length never decides; only the seam does.
  • Flagging a compound predicate, one subject with two verbs, as a run-on.
  • Missing a second-degree run-on because a joining word is present. So without its comma is still a run-on.
  • Stopping at a comma alone and calling it fixed. A comma with no FANBOYS word is a comma splice, covered in the next section.