Here are two rephrased versions suitable for a 14-year-old:
- To make the glass-blowing process clearer, sketch a small furnace with a visible open flame at the back of the house. Add a bench or shelf displaying finished glass pieces, and include a pile of sand to represent the raw material used to make glass, since this spread focuses on what things are made from.
- For a clearer depiction of the glass-blowing process, draw a compact furnace with an open flame in the rear of the house. Place some completed glass items on a bench or shelf, and show a heap of sand to indicate the material used to make glass, fitting the theme of what things are made of.