I'm not terribly familiar with that area but I know a bit about Chinese languages. HK and Macau are adjacent to Guangdong which is a Cantonese speaking province

I'm not terribly familiar with that area but I know a bit about Chinese languages. HK and Macau are adjacent to Guangdong which is a Cantonese speaking province. There are many dialects within Cantonese, so someone from Taishan will speak a dialect of Cantonese that will probably be mutually intelligible with HK Cantonese but probably also has lots of major differences. I found a cool map of them on Wikipedia: https://en.wikipedia.org/wiki/Yue_Chinese#Distribution_and_variation https://en.wikipedia.org/wiki/Yue_Chinese#Distribution_and_v... From what I know, as education improves and movement of people across large areas increases Mandarin becomes more and more common. As for movement within a Cantonese speaking area, I would guess that it might result in the adoption of a more common "standard" Cantonese over regional dialects in parallel with the increasing prevalence of Mandarin.