The system produced enough energy to heat several thousand homes.

　　系統(tǒng)產生的能量足以給幾千戶人家供暖。

　　In the exam there's sure to be a question on energy.

　　考試時準有關于能量的題目。

　　It's a waste of time and energy.

　　那是浪費時間和精力。

　　He has carried out extensive research into renewable energy sources.

　　他已經對再生能源進行了廣泛研究。

　　There has been a move away from nuclear energy.

　　人們對于原子能的看法已經轉變。