, the weight of water is oppressively heavy . 
(ROOT (S (, ,) (NP (NP (DT the) (NN weight)) (PP (IN of) (NP (NN water)))) (VP (VBZ is) (ADJP (RB oppressively) (JJ heavy))) (. .)))
(ROOT (S (, ) (NP (NP (DT ) (NN )) (PP (IN ) (NP (NN )))) (VP (VBZ ) (ADJP (RB ) (JJ ))) (. )))