Can someone give me a topic idea on what to write for a short story? exposition, rising action, and climax.

Metonymy is best defined as a figure of speech in which

This device blocks an opening along the base/floor of stairs or other walking or working surfaces where materials or body parts might otherwise inadvertently fall through. it should be 4 inches high, with not more than ¼ inch clearance above the floor

What does the line most likely show about the setting of the scene?