这里putting 和 saving 引导的都是非限制性定语从句,将整个主句作为先行词,前面实际上都省略了 which is
Trevor used it toget to work,which is putting in 60hour weeks to support his young family.
“Trevor 用它上班”这个行为 is putting in 60hour weeks to support his young family.
“and the bikewas also used to get grocerise”这个行为节省了我们的路程
建议看看非限制性定语从句的用法.1楼没解释清楚.