Subway door announcement mystery I think probably every metro system around the world has to have an audio announcement warning passengers to stay away from the train's doors as they're closing. Here in New York, a pre-recorded voice phrases it this way:　"Stand clear of the closing doors, please."

Hong Kong MTR's announcement is given three times: in Cantonese, Mandarin, and English. Working backwards, the English is similar to New York's, but worded slightly differently: “Please stand back from the doors." The Mandarin took me a little while to deduce, but I am fairly confident it is this: "請不要靠近車門" / "qing buyao kao jin chemen" / something like "please do not lean near the vehicle doors."

But my question to you is this: What is the Cantonese?  An audio file is linked at the end of this post. It seems to be one less syllable than the Mandarin, which is what I find surprising.  I don't know Cantonese Romanization conventions, so I apologize in advance for butchering this, but it sounds to me as something like：Sing ge kao gen sa mon.  That makes me think it is basically a different pronunciation of 請__靠近車門, but what in Mandarin is rendered as 不要 is condensed in Cantonese into just one syllable.  Is that right?

Here's the audio. The announcement starts about 15 seconds into the 30-second clip.

http://startsandfits.com/audio/MTRdoors-mp4.mp4

Thanks in advance for any clarity.
The word you are looking for is 勿:


  請勿靠近車門 cing2 mat6 kaau3 gan6 ce1 mun4 (Jyutping romanization)


The usage of 請勿 ("Please don't") is considered formal or literary in Cantonese, so it's not typically heard in common speech, but you'll often see it on signs or in public announcements.

EDIT: Just wanted to also add that your deduction of the Mandarin is exactly correct.