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: Bob's parents promised him a surprise if he got good grades. Sentence2: They went to the pet store. Sentence3: Bob saw a black and white puppy that he liked. Sentence4: Bob adopted the puppy and named him Spot.

Bob and Spot are best friends.