Teacher:In this task, you're given a four sentences of story written in natural language. Your job is to complete end part of the story by predicting appropriate last sentence which is coherent with the given sentences.
Teacher: Now, understand the problem? Solve this instance: Sentence1: Sara wanted to buy a book. Sentence2: Sara did not have the money for the book. Sentence3: She decided to mow the lawn for her parents to earn money. Sentence4: She mowed the lawn three times before she had earned enough.
Student:
Once she had the money, she bought the book.