To protect the environment, scientists and engineers are researching ways to ( ) electricity more cheaply from such renewable energy sources as the wind and the sun.
举一反三
- What should we do to protect the environment in daily life? A: using clean energy, such as solar energy and wind energy B: using more electricity C: reducing the cost of fund (资金) D: having more bikes
- Our energy needs will have to be fulfilled from ( ) A: depletable energy sources B: renewable energy sources C: the existing energy D: recycling energy
- Question 8Geothermal energy is one of the few energy sources that is not originally derived from the sun.
- Renewable energy includes wind power.
- Scientists are pushing known technologies to their limits in an attempt to ________ more energy from the earth.