iOS 11 default quotation mark changed to ‘ ’ and “ ” Before iOS 11, the default quotation marks were the ASCII ' and ", but now they are changed to ‘’ and “” (curly quotation marks). I have to long press the quotation mark key on the soft keyboard to type the normal ones and have no way to type them on a Smart Cover.

I’m a programmer and I have to use ' and ", is there any way to change them back?

I suspect this problem is linked to my language and region settings, I’m in China and my iPad language is English by the way.
It's in Settings | General | Keyboard | Smart Punctuation.