What visa is best for me?

Hello,

1. I have a business funded in London but need to spend some time in China 3 months or so at a time getting things manufactured.

2. I also might be taking time to study there during the summer for a language course, will this interfere with the entry permit i will get in question 1 and will they refuse to let me study since i do business in china aswell as i know students are NOT allowed to work what so ever!