In different cultures, people always have different ways to express themselves. If you don’t understand their cultures, misunderstanding will occur. 
Generally, the USA are low-context, and the Chinese are high-context. If you talk with an American and do not understand the low-context system used in the United States ,or Americans do not understand the high-context system used in China, misunderstandings will occur.
So if you invite a Chinese to do something together, they may not reject you directly. They may say a lot of things first. But if you invite an American, what they are going to do is opposite to the Chinese. They will say “Sorry， I'm tied up.”,if they have another plans.

high-context 外向的
low-context　 含蓄的