a waste 为什么要加 a,waste当名词（垃圾）讲时有复数（加s）的形式吗？

网友回答

这里的知waste是名词,固定用道法
　　a waste of sth.
　　n.
　　1.浪费;滥用[U][S][(+of)]
　　Doing such a job is a waste of his talents.
　　做这专种工作是在浪费他的属才能.

网友回答

有。例句来自柯林斯词典。
　　Up to 10 million tonnes of toxic wastes are produced every year in the UK.
　　英国每年会产生多达1,000万吨的有毒废弃物专。
　　但waste作为废属物一般是不可数的。
　　N-UNCOUNT 废物;废料Waste is material which has been used and is no longer wanted, for example because the valuable or useful part of it has been taken out.
　　Congress passed a law that regulates the disposal of waste...
　　国会通过了一项规范废弃物处理的法律。