She tries not to react but knows she has by the smirk on Frank’s face, the threat in the not-so-veiled statement plain.
It seems to me as an unusual structure. Could you please explain it to me?
Hadley & Grace by Suzanne Redfearn
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Sign up to join this communityShe tries not to react but knows she has by the smirk on Frank’s face, the threat in the not-so-veiled statement plain.
It seems to me as an unusual structure. Could you please explain it to me?
Hadley & Grace by Suzanne Redfearn
Has by is not a single expression; rather, it's the end of one and the start of another.
She tries not to react but knows she has by the smirk on Frank’s face
is in two parts:
She tries not to react but knows she has
by the smirk on Frank’s face
We might expand the sentence to make this easier to understand:
She tries not to react but knows she has reacted. She can tell that her reaction is visible by the smirk on Frank’s face.
It is not really unusual or uncommon in English. It is simply inserting a clause with the reason into the sentence. That is, it would be reasonable to write
She tries not to react but knows she has, the threat in the not-so-veiled statement plain.
Inserting "by the smirk on Frank's face" just provides the reason she knows. It could equally well be written
She tries not to react but knows she has (by the smirk on Frank’s face), the threat in the not-so-veiled statement plain.
or
She tries not to react but, by the smirk on Frank’s face, she knows she has, the threat in the not-so-veiled statement plain.
A more formal or unambiguous form would be "...but she knows she has done so by ...". In answer to questions like "have you done this" or "have you been there", some people will answer simply "yes I have" and others will answer "yes I have done" or "yes I have been". The preference may be regional; the fuller forms I associate with UK speech.