this reminds me another joke in the elevator,
one day, a man stepped into the elevator, and see a very very hot girl inside, to his surprise, the girl asked him:"going down" in English, but the man is a Chinese, the pronounciation sound like "GouYinDang" in PinYin, the man was so stunned, and squeezed a word:"Yes".
therefore, the tips in the elevator are, if you are a girl, Please say "up or down", if you have to say something..

this version is spiced up, more vivid..