Final answer:
The revision that corrects the run-on sentence is: 'I have never travelled outside of the United States, but I would like to go to Spain someday.'
Step-by-step explanation:
I have never travelled outside of the United States, but I would like to go to Spain someday. This revision corrects the run-on sentence by adding a coordinating conjunction ('but') to connect the two independent clauses. The comma before 'but' is also necessary to separate the clauses. By making this revision, the sentence becomes grammatically correct and easier to understand.
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