Clause Confusion: Run-Ons
nIncorrect: He ran 10 miles a day for a week preparing for a marathon is not easy!
nCorrect: He ran 10 miles a day for a week.  Preparing for a marathon is not easy!
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nIncorrect: But the hard work paid off he was able to finish the race in the top 100.
nCorrect: But the hard work paid off as he was able to finish the race in the top 100.
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