他们一直在背后议论我吗？

Have they been saying things about me ___behind ___my ___back?

他们经常在背后说侮辱她的话。

They often say insulting things about her ___behind ___her ___back.

这个决定是背着经理做出的。

The decision was made ___behind ___the ___manager's ___back.