Task: Story Composition
Input (English): Premise: Mary was dog sitting for a friend who was on vacation. 
 Initial Context: One day, Mary's son Simon was playing in the backyard with the dog. 
 Original Ending: Simon didn't realize that someone had left the gate open. When the dog saw the open gate, she took off running after a rabbit. Simon was able to catch her when she stopped to sniff a fire hydrant. 
 New ending: Simon didn't realized that someone left the gate to the stairs open. When the dog saw the open gate, she tried to go down the stairs and fell. Simon was able to get to her and see that she was ok. 
Output (English): One day, Mary's son Simon was playing upstairs with the dog.