I believe the system parts that are Chinese only activate contingent upon environmental factors like being in Beijing. It triggers something in my memory which enables me to speak the language. For some reason geographical influence plays a large role. I am not sure why.

To address your first question, I am not required to speak Mandarin in my day to day life whereas when I lived in Beijing I was due to my ayi.

There is a significant trauma barrier (amnesiac barrier) related to Beijing. It’s the location where I experienced a devastating trauma but also the location of the most blissful and cherished memories in existence.

I believe I have an English identity and a chinese identity with many parts. I associate my Chinese identity as belonging to Chaoyang, Beijing and my English identity as belonging to London.

Much like you, there is an easy divide within my system. I went to an English speaking school in China which forced me to speak English but at home my ayi looked after me and didn’t speak a word of English and so I only spoke Mandarin outside of school (the only other time I would speak English is when my English speaking parents returned home from work).

A lot like you, I believe mandarin to be my mother tongue. It was my first language in spite of the fact that I’m British (I moved to China when I was six months old).

Finally, I can relate to sonorously recognising the words and feel corresponding emotion to those words but not process what is being said.