It so happened that the cellist graduated last year.

碰巧这位大提琴手去年毕业了。

I saw him yesterday, as it happens.; it so happened that I saw him yesterday.

碰巧我昨天看见了他。

It so happened that both of them were there.

可巧他们两人都在那儿。

It so happened that he was going that way too.

如此碰巧的是他也往那边走。

Once it so happened that a rat fell into a jar.

一次，有一只老鼠忽然掉人瓮中。