1. What is a run-on?
A run-on is a sentence that contains two independent clauses, in other words, a sentence that is really two sentences in one.

2. How to fix a run-on sentence:
Break it apart into two sentences
Ex. Run-on: The weather was bad, the meeting was poorly attended.
Correct: The weather was bad. The meeting was poorly attended.

3. How to fix a run-on sentence:
2. Add a semi-colon if the two ideas are closely related.
Ex. Run-on: The weather was bad, the meeting was poorly attended.
Correct: The weather was bad; the meeting was poorly attended.

4. How to fix a run-on sentence:
3. Add a comma and a conjunction Ex. Run-on: The weather was bad, the meeting was poorly attended. Correct: The weather was bad, therefore, the meeting was poorly attended.

5. How to fix a run-on sentence:
4. Re-word it to make one clause dependent
Ex. Run-on: The weather was bad, the meeting was poorly attended.
Correct: Because the weather was bad, the meeting was poorly attended.