yup! you are right, in Cantonese 好substitute 很，都or 又substitute 也 ，係or 系or 喺 substitutewrited 是。Cantonese use words as mandarine. the most difference is pronunciation,and there is some difference in actual usage. in Hongkong and Macau, the people used traditional chinese for Cantonese. the people live in guangdong who speak Cantonese use simple chinese for Cantonese. You may learn mandarine mainly. Cantonese is more harder than mandarine in pronunciation, and most of the people who speak cantonese can understand mandarine except for some old people.

Sorry, my latest post isn't easy to read like this.. ^^ --- 佢哋嘅 (keui dei ge) = 他们的; 唔係 (m hai) = 不是; 冇 (mou) = 没有

Don't worry, there aren't too many "Cantonese characters" like this. I used to chat with Hongkongers in the past and learned many of these. Like〉 佢哋嘅 (keui dei ge) = 他们的 唔係 (m hai) = 不是 冇 (mou) = 没有

这些字一般用在广东话的口语中。