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.