废酸的英文：
spent acid
waste acid
adj. 精疲力竭的；用过的，不再有用的
v. spend的过去式及过去分词形式；花费
Money spent on the Brain is never spent in vain
智力投资,决非虚掷
He spent money lavishly.
他花钱大手大脚。
The night was spent in prayer.
整个晚上都在祷告。
n.
1.[U,C]【化】酸
2.[U] 酸味物质
adj.
1.【术语】酸的；酸性的
2. 酸的；酸味的
3.（言辞）尖刻的；尖酸的
The somewhat acid flavour is caused by the presence of lactic acid.
这种微酸的味道是因为含有乳酸造成的。
Acids in the stomach destroy the virus.
胃酸能杀死病毒。
suffer from acidity of the stomach
患胃酸过多.
v. 浪费，滥用，消耗
n. 浪费，废（弃）物，废料，排泄物
adj. 废弃的，无用的
It would be a grievous waste.
那将是一种严重的浪费。
This opportunity is too good to waste.
这个机遇千载难逢，绝不能错过。
"Waste not, want not "
俭则不匮