Why no 'it' here? ("it" before/after the "is")

[Liqichao]

Hello,

I have a problem with below sentence, why no 'it' after 'is'? Thank you for your help.

In Japanese is not at all as common to use as the English phrase "How are you".

[Kitosdad]

" it " before the is would be the correct placement here.

" it " after the is would need a question mark at the end of the sentence. It would then form a proper sentence.
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