网友说的单数、复数，应该是指谓语动词 has been growing，还是 have been growing 吧？

While the recycling of constrcution waste and tyres have both been growing, both industries continue to generate significantly more waste than is currently reused. （误）

While the recycling of constrcution waste and tyres has both been growing, both industries continue to generate significantly more waste than is currently reused.（正）

1. while 从句中，主语中心词是 the recycling，而of ...定语中的复数名词，不影响使用单数谓语动词。

2.  than is currently reused 是比较状语从句。than 看作比较代词，指代前文被比较项 more 所修饰的 waste，同时作从句的主语。

其他都很简单。