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: I was walking down the street. I suddenly saw a boy crying. I asked him what was wrong. He told me that his balloon floated away. I bought him a new balloon and he was happy.
 selected sentence: I bought him a new balloon and he was happy.

I decide to buy a balloon >Causes/Enables> I buy the balloon