What kind of challenges a business expatriate would face in China?

Culture and language are the obvious answers (although many people speak English in China, especially in Beijing and Shanghai). Some of the challenges specifically faced by a business expatriate I think would be:

1) Vastly different management style between Western companies and Chinese ones

2) Compliance with Chinese business regulations and requirements, which are also very different from the West

3) Individual compliance with tax laws both in China and the expat's home country

4) If in the business of selling things to individual customers, understanding the Chinese consumer

5) Quality control and inspection if you will have a Chinese manufacturing partner

6) Intellectual property protection

7) Balancing doing things the "Chinese" way but also bringing in their own Western experience and training

8) Curiosity and increased attention from your colleagues as an "outsider"

The language

Mainly Language and cultural barriers

Language/culture barrier, Physical abnormality (compared to everyone else who looked similar), Money/Social gap between China and wherever he/she came from, etc.

-Sanitation

-cultural differences