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: Bret decided to bake his own bread. Sentence2: He mixed the dough carefully. Sentence3: But when he pulled the bread out of the oven, he frowned. Sentence4: The bread had not risen!

Bret realized he had forgotten the yeast!