to do 和done 的有关疑惑

Increased efforts by green groups ______ the public about the benefits of recycling have also helped.

老师，这边的by，不是表示方法，而是表示这类努力的推行者吧，但如何看不到被动的存在？这里的空 为何不能填educated，表示已经完成的动作，而是to educate呢？

网友为什么不仔细考虑，能填 educated 吗？填了它谓语 have helped 如何解决？

Increased effortsby green groups to educate the public about the benefits of recycling have also helped.

1. 察看句子必须要“瞻前顾后，统筹把握”，红色部分是句子的主干：主语+谓语。

2. 介词by 引出动作的施事者，但动作可以省略不说。比如：

a book by John = a book written by John

Increased effortsbygreen groups =Increased efforts madebygreen groups

3.to educate ...作定语，修饰efforts。大家常说：make great efforts to do sht. ，其中to do sth. 就是定语。