Given the task definition and input, reply with output. 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.

Sentence1: Katy's cell phone was broken. Sentence2: Katy decided to go to the mall to get a new one. Sentence3: She drove to the mall and went to the mobile phone store. Sentence4: Katy looked at a bunch of phone until she found that was just right.
She then purchased the phone and started making calls.