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: Greg had just listened to a very popular song. Sentence 2: After a couple of hours he realized it was stuck in his head. Sentence 3: He kept humming the song for weeks on end. Sentence 4: After a couple of weeks, Greg heard another popular song. Sentence 5: Now that song's stuck in his head.

Song