For a truly "deep" physical piece, structural engineering focuses on the substructure that anchors a span.
Large bridges rely on piles —long shafts of concrete, timber, or steel—driven hundreds of feet into the ground to reach stable soil. Bridge!
Use the bridge to move from the "past" of the verses and the "present" of the chorus into the "future"—what the character will do next. For a truly "deep" physical piece, structural engineering
