About 同居, there were two posts in mingpao yesterday,
http://hk.news.yahoo.com/050817/12/1fokg.html
http://hk.news.yahoo.com/050817/12/1fokf.html

The radio programme, 千禧年代, also talked about this news yesterday. I agree that living together enables to know more about each other. "別以為同居時既問題係婚後唔會緩和, 只會加劇”