花费精力

消耗能量

excess energy───过剩能量；[能源]多余能量

extra energy───额外能量

green energy───绿色能源

wind energy───风能

reduced energy───减少的能量

explosive energy───爆炸能量；炸药爆炸功

cheap energy───廉价能源

clean energy───清洁能源

expediency───n.方便，权宜；私利；权宜之计

Cars must carry their energy and expend energy to carry it so the less weight per unit of energy the better.───汽车必须携带能量而这本身就需要消耗能量，因此单位能量的重量越低越好。

They do not want to expend energy in what, to them, is a lost cause.───他们不想把精力投到他们认为注定不会成功的事中去。

They do not want to expend energy in what, to them, is a lost cause.───他们不想再费精力了，对他们而言，那是注意定要失败的。

What we know less about is why some people expend energy in short bursts while others sustain much longer bursts.

They do not want to expend energy in what, to them, is a lost cause.

Deciding - consciously or not - to expend energy involves a choice and an assessment of the total energy available.