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: Ben's older sister ran away from home. Sentence2: Ben's parents spent months looking for her. Sentence3: The police dropped by the house from time to time, with no news. Sentence4: Ben went into his sister's room and looked at all she left behind.
Student:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
He wondered if he would ever see his sister again.