房子背后

behind the house

山背后

behind the mountain

躲到别人背后

hide behind others

听到背后有脚步声。

I can hear the sound of footsteps behind me.

背后戳一刀

stab someone in the back

当面讲的是一套, 背后讲的又是一套。

Saying something to someone's face is one thing, talking about someone behind their back is another thing.

不要在背后议论

don't discuss it behind their back

这件事背后另有原因。

There is another reason for this behind the scenes.