事情既然发生了，这就是命。

That happens. That's life.

youdao

既然发生了那样的事情，我们决定取消那次预定的会议。

After what had happened, we decided to call off the scheduled meeting.

youdao

既然事情已经发生了，就没有后悔的余地了。

Now those things have happened, there is no room for regret.

youdao

It's not taking place in this life, so it has to have happened before.

既然不是这辈子发生的,那么就肯定是以前发生的

耶鲁公开课 - 死亡课程节选