Task: Story Composition
Input (English): Premise: Nancy was swimming in the ocean. 
 Initial Context: She saw a large fin rise from the water. 
 Original Ending: She got scared and tried to swim as fast as she can to the shore. Jenny had to help her get up since she had breathing problems. Terry rose from the water, with the toy fin on his head. 
 Counterfactual Context: She saw a large fin rise from the water and it was a real shark.
Output (English): She got scared and tried to swim as fast as she can to the shore. Jenny had to help her get up since she had breathing problems. Terry rose from the water and ran.