Task: Story Composition
Input (English): Premise: Jack did not know how to swim. 
 Initial Context: He had gone all his life without knowing how. 
 Original Ending: He wanted to go snorkeling with his marine bio class. He told his professor his predicament. His professor agreed to give him private swim lessons before the trip. 
 Counterfactual Context: He had gone all his life knowing how.
Output (English): He wanted to go snorkeling with his marine bio class. He told his professor his predicament. His professor agreed to give him private swim lessons before the trip.