Final answer:
A run-on sentence is a sentence that combines multiple independent clauses without proper punctuation or conjunctions to separate them.
Step-by-step explanation:
The group of words that is a run-on sentence is: The babysitter sat on the bench she ate a snack. A run-on sentence is a sentence that combines multiple independent clauses without proper punctuation or conjunctions to separate them. In this case, the two independent clauses 'The babysitter sat on the bench' and 'she ate a snack' are incorrectly fused together without any punctuation or conjunction. To fix this run-on sentence, we can add a period or a coordinating conjunction to separate the two clauses, for example: 'The babysitter sat on the bench. She ate a snack.' or 'The babysitter sat on the bench, and she ate a snack.'
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