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: Ben wanted a new carpet. Sentence2: But he could not decide which color to buy. Sentence3: His friend recommended white. Sentence4: So Ben had a white carpet installed.

But he found that it was difficult to keep looking clean.