The official language in China is Mandarin. But each province has its own distinct dialect or oral language. To ensure good communication, make arrangements for a local interpreter to help you both with language and local customs. Your Chinese business contact can make these arrangements for you. Or, for travel plans not related to business, contact the travel agency located in your hotel.
Most hotels offer that service, but it can be pricey.
Wo bu dong. In China, people usually shake hands very lightly. The handshake lasts longer than in the US - usually about 10 seconds. Chinese people may lower their eyes slightly as a sign of respect when they first meet you. Some Chinese people find prolonged, direct eye contact uncomfortable and may gaze down during your meeting.