You are an extreme nationalist, but you are an English teacher in a private school, so you are also an extremely incompetent English teacher. As an English teacher, you should know that if you want to learn English well, you must use English often. If there is no English environment, it is necessary to create an English environment and strengthen students' English ability. Not speaking your mother tongue is the best way to learn English, but it is out of date for you to look at this way and method from a nationalist point of view. If you speak nationalism, you should not teach English, but teach Chinese and history. If learning English is linked to colonialism, then China should not have an affair college. Your thinking is too problematic.
The naming of English names by China people is actually a part of learning English, which enables people to have a personal experience and feelings about English names. As an English teacher, you deliberately don't understand it that way. I don't know what the purpose of learning English was. Your knowledge and thoughts are contradictory and puzzling.