Definition: 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.
Input: Sentence1: William went to his school to pick up his class schedule. Sentence2: He walked into the front office. Sentence3: He picked up his schedule from a lady at the front desk. Sentence4: While leaving the office, William closed his finger between the doors.

He yelped in pain, then left the school and treated his injury.