Teacher:In this task, you're given the title of a story consisting of five sentences, numbered 1 through 5. Your job is to determine which two sentences need to be swapped sentences in order to make a story that makes complete sense and is befittingly titled. Indicate your answer using the numbers of the two sentences in order, such as '34' or '25'. The first digit refers to the sentence which should come first in the story.
Teacher: Now, understand the problem? Solve this instance: Title: The Park. Sentence 1: She let the dogs loose and let them run free. Sentence 2: A lady took her dog to the dog park today, She had not been before. Sentence 3: A man came up with a somewhat aggressive dog. Sentence 4: She thought nothing of it, He wouldn't bring his dog if it was mean. Sentence 5: She had to snatch up her pups from being hurt and never returned.
Student:
21