( ( ( 317-3 Fluids ) ( exert bigger ) ) ( up ( ( forces ( on ( lighter objects ) ) ) . ) ) )
(ROOT (S (NP (NP (CD 317-3) (NNS Fluids)) (ADJP (JJ exert) (JJR bigger))) (ADVP (RB up)) (VP (VBZ forces) (PP (IN on) (NP (JJR lighter) (NNS objects)))) (. .)))
317-3 Fluids exert bigger up forces on lighter objects.
(ROOT (S (NP (JJ Bouyant) (NN force)) (VP (VBZ is) (NP (NP (DT the) (JJ upward) (NN force)) (VP (VBN exerted) (PP (IN by) (NP (NP (NNS fluids)) (SBAR (WHADVP (WRB when)) (S (NP (NP (DT any) (NN object)) (, ,) (PP (JJ such) (IN as) (NP (DT a) (NN boat))) (, ,)) (VP (VBZ is) (VP (VBN placed) (PP (IN in) (NP (PRP it)))))))))))) (. .)))