'Hei se hui' - A bad idea
On second thought, this wearing black thing is not a good idea after all. Imaging when there are so many young men and women wearing black and some may be mistaken for being members of a new secret society. Then all it needs is a staring incident and fighting can start. Hei se hui is literary Black Society or meaning secret society in the Chinese lingo. This black shirt thing can become a serious threat to peace. No good, no good. It is worst than mass cycling. Better change to a better colour.