some day,a day和one day的区别

问题描述:

some day,a day和one day的区别

some day 将来的某天,e.g.I'll come back some day.
one day 和a day 在针对“一天”来说几乎相同.
one day 也可指过去的某天,或将来的某天.
e.g.One day,.(好多故事都这么开篇吧)
He'll come to realize it one day.