one day等于some day还是 the other day?

One day ,a farmer and a snake.....
I will achieve my dreame one day/some day
I met my ex-girlfriend the other day.(several days ago)
请认真体会以上句子,你会搞懂的!

one day（将来）有一天；总有一天；（过去）某一天
some day总有一天；将来有一天；来日
the other day不久前某一天；几天以前

one day(过去或将来)某一天
例句：I am sure he will succeed one day or another.我确信某一天他会成功的.
some day 将来有一天
例句：I can come back to my hometown some day.总有一天我会回到家乡.
one day与some day都可作“某一天”解,但两者的用法有所区别.one day:on a day(past or future) some day:on some day in the future 意思也就是说,one day既可指过去,又可指将来;而some day只能指将来
the other day 前些日子,前几天,那天
例句：I'm sorry about the other day.前几天真是很抱歉.
the other +表示时间的名词通常只与过去时态连用.