Task: Sentence Ordering
Input (English): Sentence1: Then he came upon some paper scraps on the floor. Sentence2: His dog, Betty, was sitting nearby with a paper scrap in her mouth. Sentence3: John had worked hard on his homework but couldn't find it anywhere. Sentence4: John was worried his teacher would think he was lying. Sentence5: John didn't know what to do.
Output (English): 23145