新概念英语3第23课的问题

题目

新概念英语3第23课的问题
第一段最后一句the sad truth is that most of us have been brought up to eat certain food and we stick to them all our lives 中lives前面为什么不用加介词?

答案

all one's life 固定用法.还有就是用 物主代词our,后面就不能用冠词了.