Here is an article written by Daisann McLane, who has learnt Cantonese for a period of time. 係、啦、都 with all 9 tones actaully represent different words in Chinese and of course has different meaning. The author find it interesting to learn Cantonese although these words sometimes confuse her. She found that the language is "Cantonese is like Italian to Mandarin's German.".
It's interesting to see how the other sees us, including our language.