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: Elizabeth couldn't wait for her son Sam to take his first steps. She was determined to capture the moment on camera. She wanted to make sure she remembered it perfectly forever. But when Sam finally took his first steps, the camera wasn't charged. Elizabeth didn't mind that much - she knew she'd remember anyway.
 selected sentence: But when Sam finally took his first steps, the camera wasn't charged.

Elizabeth forgets to charge the camera >Causes/Enables> The camera isn't charged