Definition: In this task, you will be given a short story. One sentence from the story is chosen. Consider the events that happen before that sentence, or are likely to have happened before it. Does any of them directly cause it, or simply make it possible? You should write your answer in the form " A >causes/enables> B". Try to use phrases and sentences from the story to compose your answer when possible.
Input: story: John went for a walk. He walked to the park. There was a guy mowing the lawn. He waved at John. John waved back.
 selected sentence: There was a guy mowing the lawn.

John walked to the park >Causes/Enables> John saw a man mowing his lawn 