Chinese language

I know this much: Cantonese and Mandarin, at least, are not mutually intelligible.

No, it's not possible for, say, a Cantonese speaker to communicate with a Hokkien speaker, assuming that neither know the other dialect. The sounds are different, and there are many phrases and slang words in a dialect that do not appear in another. The only thing that is similar is the writing, though again, there are characters that appear only in one dialect.

But when spoken in its pure form (without phrases/slang) it is possible to translate the words directly from one dialect to another by simply changing its pronunciation.

I'm from China. Most people in China can speak mandarin, they can communicate with each other with no difficulty. But China is a big country you know, so people living in different places have their own culture and habits, with the long history, people in different area may have their own manners to intercommunicate, expecially in the language. In China, people living in the north can hardly understand what the people say who is living in the south, if he don't say mandarin. But this difference is not like between French and German, French and German are totally two different languages.

mandarin is the basic language in China.
if you master mandarin,you can communicate with most people in China

cantonese is the language use in Hong Kong.

Mandarin is the language use in China and Taiwan.

Are there not any left over distinct languages in China, in any province?