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: Nick took his dog for a walk last Saturday. Sentence2: During the walk, his dog saw several other dogs. Sentence3: He was not well-socialized, so he started barking at them. Sentence4: It was a long and painful experience for both of them.

Nick decided to take his dog to a trainer.