For four years.
Q: How did you get the idea of making free lunches?
A: Four summers ago, I didn't want to go camping. Instead, I did an online treasure-hunt programme. My first task was to do something to help homeless people, and I got the idea of making them lunch.
问:你是怎么想到做免费午餐的?
答:四年前的夏天,我不想去露营。代替地,我参加了一个在线寻宝项目。我的第一个任务是做一些事情来帮助无家可归的人,于是我有了给他们做午餐的想法。
可知利亚姆从四年前开始发放免费午餐,故答案为:For four years.