It's been a long time that I use English, no mention French.
Since I am from Taiwan. I live here and work here.
Language is just for communication. I don't have any needs to communicate in different language.
That isn't totally correct.
Indeed, sometimes I reply some email in English. Most of them are the things that might be impolite when say it in Chinese. Or something that I don't know how to say it to my bosses.
I think the Sociolinguistics may have an analyse for this act.
It's time to bed.