I can't type Chinese on my mac!! - MAC

I don't know why,

yesterday, I want to use my mac,

but I found I can't type Chinese.

I check my caps lock,

and press command + space to change my input into Chinese,

It still can't work.

I also try to turn off my mac,

It's useless as well.

Plz, help me....... I really need to type Chinese for my mid-term papers.


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