energy本身就是名词。energy的基本意思是“活力”“干劲”“能力”，多用作不可数名词，在指人的“精力”时多用复数形式。引申可表示“能”“能量”“能源”。

energy的用法例句

1. At 54 years old her energy and looks are magnificent.

她54岁了，精力和气色都非常好。

2. Revenues from "green taxes" could then be channelled back into energyefficiency.

从“绿色税收”得来的收入便可回过头来用于提高能效。

3. Brazil says its constitution forbids the private ownership of energy assets.

巴西称其宪法禁止个人占有能源资产。

4. He told Americans that solving the energy problem was very important.

他告诉美国人解决能源问题非常重要。

5. We couldn't even summon up the energy to open the envelope.

我们甚至连打开信封的力气都没有了。