Differences between Chinese and American culture

Although Hong Kong was colonized by Britan for over hundred years, many people still remain old Chinese traditions. Today, I still remember the way  my elementry school teachers treated me when i had done something "seriously bad" from their point of view. For instant, at my third grade of elementry school, if I did bad on exams or if i missed any homeworks, he would either hit my hand hardly with his big, thick, and hard-made plastic ruler or twist my ear into "different shapes" than my origianl shape which was painful (this kind of tradition hopefully does not exist anymore).  In the U.S., my years of high school, perhaps to any grade, any form of physical punishments is not allowed. Also, as a student in Hong Kong, you barely see students talking with their teachers like friends. However, in here, teachers are like friends and teachers more than just teachers. One big difference in schools between Hong Kong and China is that students in Hong Kong have to bow in humble reverence to teachers but in the U.S., they do not need to bow in reverence. In H.K., when your teachers are pointing out and correcting your mistakes or some behaves, you can not look into their eyes directly because that is disrespectful, instead, you should look downward. In the U.S.,  In the public, if you live in Hong Kong long enough, you will notice that no one will hold doors for the following person. However, in the U.S., people will hold doors for the following person.