Task: Sentence Ordering
Input (English): Sentence1: The veterinarian, Doctor Mike, found three fleas on Lee. Sentence2: Jen brought her cat Lee to the vet for a checkup. Sentence3: Doctor Mike suggested a flea dip to Jen. Sentence4: Jen noticed that Lee's flea problem quickly got worse. Sentence5: Jen refused because she did not want Lee to be dipped in chemicals.
Output (English): 21354