That couldn't happen in a sane world, either.
( That ( ( ( could n't ) ( ( ( happen ( in ( a ( sane world ) ) ) ) , ) either ) ) . ) )
(ROOT (S (NP (DT That)) (VP (MD could) (RB n't) (VP (VB happen) (PP (IN in) (NP (DT a) (JJ sane) (NN world))) (, ,) (ADVP (RB either)))) (. .)))
That could definitely happen in a sane world.
( That ( ( ( could definitely ) ( happen ( in ( a ( sane world ) ) ) ) ) . ) )
(ROOT (S (NP (DT That)) (VP (MD could) (ADVP (RB definitely)) (VP (VB happen) (PP (IN in) (NP (DT a) (JJ sane) (NN world))))) (. .)))