"Diu Nei Lo Mo!" ("fuck your
mother") is a highly offensive profanity in Cantonese when directed against a specific person instead of used as a general exclamation. In contrast to the English phrase "fuck your
mother", which indicates that the person being attacked commits incest with his own
mother, the Cantonese expression has the implied meaning of "I fuck your mother".
Peter: "This
song reminds me of my girlfriend back in Guangzhou."
Joel: "That
song reminds me of your girlfriend too, if you know what I
mean."
Peter: "DIU NEI LO MO!"