Plumbing and electrical grid: what they have in common
- Step 1. Plumbing — has part — Water tower. Maintaining pressure.
- Step 2. Water tower — is made of — Brick. Water towers are brick.
- Step 3. Brick — is material for — Power station. The buildings of the first power stations were brick.
- Step 4. Power station — is part of — Electrical grid. Power stations feed the grid.