i was at church on sunday .i was at the office on monday.为什么一个用the,一个不用

问题描述:

i was at church on sunday .i was at the office on monday.为什么一个用the,一个不用

at church 不单是指在教堂,还有"做礼拜"的意思
at the office 指的就是星期一作者所在的方位