Problem typing bracket in Chinese Pinyin
A few months ago after I've upgraded to macOS Sierra, I found that I was unable to type the bracket "「" or "」" when I was typing in Traditional Chinese clicking on "[" and "]" on the keyboard, which usually did show them properly when it was El Capitan. I ended up having to use shift+option+B to call out a menu which has all Chinese symbols included and select the brackets there, which I found quite annoying. However, I found that if I use other Chinese input method instead(Zhuyin), the bracket is properly shown again, which I guess it's something wrong with Chinese Pinyin.
So, is there a way to fix it without re-installing the entire system? Am I able to modify any file containing the Chinese input method and to change "[" back to "「"? Or to do any other things which require higher permission? Would be appreciate if anyone can help, thanks.
MacBook Air, iOS 10.2.1, early 2015