electricity
저자: Guo haoyi
1. a packet of electricity
1.1. batteries
1.1.1. chemicals
2. gives us power
2.1. flows through wires
2.1.1. are connected to cables
2.1.1.1. a power station
1.1.1. chemicals
2.1.1. are connected to cables
2.1.1.1. a power station