接受礼物时，说“多謝”。 接受帮助时，说“唔該”。

I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
This is the standard way of saying “thank you” in Cantonese.  Cantonese is spoken mainly within southern China. Outside of mainland China, it is spoken by most people living in Hong Kong and Macau. It is also spoken within many overseas Chinese communities in Southeast Asia, Canada, Brazil, Peru, Cuba, Panama, Australia, New Zealand, Europe, and the United States. Even though this is the most common way of saying “thanks” in Cantonese, it is almost always used in response to thanking for someone