Definition: In this task, you're given five sentences, numbered 1 through 5. Your job is to generate a title for the story that makes complete sense. The title must be short, with less than three words, use simple language, and include the main topic of the story.
Input: Sentence 1: Shout had a friend for four years. Sentence 2: They were very close. Sentence 3: All the sudden her friend stopped talking to her. Sentence 4: Shout was very upset. Sentence 5: She didn't know what to do.

Lost friend