As an English teacher, I have noticed that China Chinese (pardon me, this is a problem only for the Chinese from China) have the wrong attitude towards learning English. In general, they prefer to memorize English vocabulary and sentence structures to learning how to express themselves and portray the correct meaning. They feel that it is sufficient to understand and make themselves understood. This attitude is the main cause of the lack of politeness when communicating in English as mentioned by H-five.
The first few Chinese started learning English to communicate with foreigners. They had little time to make do with and it is understandable for them to have the attitude of learning I mentioned above. However, our generation of Chinese should not have this attitude. They have sufficient time to learn and they have the proper teachers and facilities to learn it well. As for myself, I have taken high-paying assignments to teach Chinese students English and their parents are very willing to pay as long as their children show improvement. I regret to say that their children showed little improvement as they were exam-oriented. They were not willing to spend the time and effort to learn English as they had for Chinese.
Both English and Chinese are languages and both will expect the same amount of time and dedication to excel in. If you need to learn different ways of expressing yourself in Chinese then it would be the same for English. The only way to excel in English is to give it the same attitude you would have when learning your mother tongue.