Phonetic form
In the field of linguistics , specifically in syntax , phonetic form ( PF ) , also known as phonological form or the articulatory-perceptual ( A-P ) system , is a certain level of mental representation of a linguistic expression , derived from surface structure , and related to Logical Form . 
<triplet> linguistics <subj> syntax <obj> has part <triplet> syntax <subj> linguistics <obj> part of <triplet> Logical Form <subj> mental representation <obj> instance of