oblivious

"Chinese" can mean the written OR the spoken language. It can also be used to describe people who are born of this descent. # _; A* w* Z4 J$ M
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i.e. Can you read Chinese? <-- written
/ a/ q" x0 U8 b% L( d5 B2 z* Ctvb now,tvbnow,bttvbDo you speak Chinese? <-- spoken5.39.217.763 O0 E- @+ Z5 r5 x+ `
Are you Chinese? <-- adjective. ]5 I% Q+ _# M5 }
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Since this series takes place in an era of HK before the late 1990s (before it is officially returned as a part of China), "Chinese" can be loosely used to mean Cantonese, since Mandarin hasn't been established as a common dialect of China yet. On the other hand, Cantonese is the predominant language of the local area. So, I think what 松哥 said is acceptable.