Take him upstairs, you two, and lock him up in his bedroom, while we arrange matters between ourselves.

你们两个把他带到楼上去，把他锁在他的卧室里，然后我们自己安排一下这件事。

We must draw a clear distinction between ourselves and the enemy.

我们必须分清敌我。

Let this be between ourselves.

这件事不要让别人知道。

It is a secret between ourselves.

它是我们之间的秘密。

Between ourselves, he won't live long.

这事我们私下说说，他活不了多久了。