The coal provides energy to power the (heat) （） system of hospitals.
举一反三
- The coal provides energy to the (heat) ____system of hospitals.
- Coal mining industry in Britain provides _______ of the energy consumed in the country.
- Heat energy and energy are the middle processes of energy transformation in an electric power plant.
- Heat energy and energy are the middle processes of energy transformation in an electric power plant. (chemical / mechanical)
- Heat energy is a source of power， but （） will cause damage to the engine.