Jyutping
mou5 beng6 aa3 nei5
Pinyin
mǎo bìng ya nǐ
Definitions (粵典–words.hk)
語句
表示對某人所做嘅嘢難以置信同反感，同字面上表示對對方健康關心嘅意思並無關 are you mental? despite this sounds a concern on one's health, this is to express disbelieve or disgust at someone has done