Market Theme has been designed so that all words and phrases used in the website are all locatd in one file named "mkt_language".

So, alll you have to do is translate the words in this one file — and the entire customer website will be populated into that language.

Other than that, the WordPress administration dashboard (which your customers do not see — only you see it) will need to have a "wordpress translator plugin" that will translate your WordPress administration pages into Chinese. (if you need the administration translated that is.)