It is at the moment of maximum audience susceptibility that we hear, for the first time, that the woman was fired not because of her gender but because of her sexual preference.
( It ( ( ( is ( at ( ( the moment ) ( of ( maximum ( audience susceptibility ) ) ) ) ) ) ( that ( we ( ( ( ( hear , ) ( for ( the ( first time ) ) ) ) , ) ( that ( ( the woman ) ( was ( fired ( not ( ( ( because ( of ( her gender ) ) ) but ) ( because ( of ( her ( sexual preference ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ is) (PP (IN at) (NP (NP (DT the) (NN moment)) (PP (IN of) (NP (JJ maximum) (NN audience) (NN susceptibility))))) (SBAR (IN that) (S (NP (PRP we)) (VP (VBP hear) (, ,) (PP (IN for) (NP (DT the) (JJ first) (NN time))) (, ,) (SBAR (IN that) (S (NP (DT the) (NN woman)) (VP (VBD was) (VP (VBN fired) (PP (RB not) (PP (RB because) (IN of) (NP (PRP$ her) (NN gender))) (CC but) (PP (RB because) (IN of) (NP (PRP$ her) (JJ sexual) (NN preference)))))))))))) (. .)))
The woman was fired not for her sexual preference but purely on the basis of gender.
( ( The woman ) ( ( was ( ( ( fired ( not ( for ( her ( sexual preference ) ) ) ) ) but ) ( purely ( on ( ( the basis ) ( of gender ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN woman)) (VP (VBD was) (VP (VP (VBN fired) (PP (RB not) (IN for) (NP (PRP$ her) (JJ sexual) (NN preference)))) (CC but) (VP (VBN purely) (PP (IN on) (NP (NP (DT the) (NN basis)) (PP (IN of) (NP (NN gender)))))))) (. .)))