Task: Story Composition
Input (English): Premise: David needed an office chair. 
 Initial Context: So he went to an office store and looked. 
 Original Ending: But they were all so expensive. He decided to pick up a cheap one on a Chinese website. But it fell apart after a few weeks. 
 Counterfactual Context: So he went to an office store and bought one.
Output (English): It was so expensive, they all were. He had thought about getting a cheap one from a Chinese website. But he thought it would fall apart after a few weeks.