play a role in后面接动词时，要用doing。
说明：
play a role in 意思是“在……中起作用；参与；在……中扮演角色”，in是个介词，后接名词、代词或动名词作介词宾语。例如：
The media played animportant role in the last election.
大众传媒在上次选举中发挥了重要作用。
This film is very famous, and he played a role in it.
这部影片很有名，他在影片中扮演了主角。
We can all play a role in reducing our dependence on plastic, if we started to take some small steps in our everyday lives to be mindful of our plastic use.
如果我们开始在每天的生活中采取一些小措施来留意我们对塑料的使用，我们就可以在减少塑料依赖性中发挥作用。