Teacher:Given a premise, an initial context, an original ending, and a new ending, the task is to generate the counterfactual context that is aligned with the new ending. Each instance consists of a five-sentence story. The premise is the first sentence of a story, and the second sentence, which is the initial context, provides more information about the story's context. The original ending is the last three sentences of the story. Also, you are given a new ending that can provide the new story with the same premise. You should write a counterfactual context to explain the small differences between the original and new endings. More specifically, a story context contains the general plot of the story. And a counterfactual context is a slight modification to the initial context. To sum up, you should write the second sentence of a story based on the premise(first sentence) and the new ending(last three sentences) of the story.
Teacher: Now, understand the problem? Solve this instance: Premise: Megan and Blake were highschool sweethearts. 
 Initial Context: They dated off and on for 12 years. 
 Original Ending: Everyone always knew they would get married. Blake waited until their 15th year anniversary to pop the question. Megan said yes she would marry him. 
 New ending: Everyone always knew they would get married. They got back together, and on their 15th year anniversary he popped the question. Megan said yes she would marry him. 
Student:
They broke up one year after their 6th anniversary.