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: An archeologist was studying some old ruins. Sentence2: His team discovered an old tunnel and decided to explore it. Sentence3: When they entered the tunnel, they found a large barrier. Sentence4: They grabbed some dynamite and blew the entrance open.

When they opened the wall, they saw that the tunnel was empty.