Your two sentence horror story must have a
setting (waar),
characters (wie), and a descriptive plot (beschrijvende verhaallijn), just like a full-length story, so do some brainstorming:
WHO are the main characters? How are they described in your story?
WHAT is the scary story about? What is the problem?
WHEN does this story take place? Time of day, time of year or season, and is it in the past, present or future?
WHERE does the story take place? How is the setting described in the story?
WHY is the main character in danger? Is it resolved?