The error in the sentence that should be corrected while revising is the run-on sentence.
A run-on sentence has at least two parts, both of which can stand by themselves. For example, we could say, "The ship was enormous." and "Its mast was almost 40 feet high." Both sentences are correct. In order to correct the run-on sentence, we could separate the two sentences with a period (like shown earlier) or we can add a semi-colon, so the sentence would read, "The ship was enormous; its mast was almost 40 feet high.
