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: Sam read that his favorite author wrote a new book. The book was going to be on sale in two days. Sam set up camp outside the store to be first in line. He waited until the big day. Once the doors opened he ran to the shelves and got a book.
 selected sentence: He waited until the big day.

Sam wants a book >Causes/Enables> Sam waits until the book goes on sale