Definition
A warning that one should be careful about what they say because other people might be listening.
隔牆有耳（警告勿在公開场合說話）
We should speak quietly here; walls have ears, you know.
我們在這裡應該小聲說話；隔牆有耳，你知道的。
Be careful when discussing this in the office, walls have ears.
在辦公室討論這件事要小心，隔牆有耳。
I don't want to say too much here; walls have ears, you know.
我不想在這裡說太多；隔牆有耳，你知道的。