( ( ( The gas ) ( ( arriving quickly ) ( at ( the surface ) ) ) ) ( ( creates ( ( ( a ( ( very low ) ( density fluid ) ) ) and ) ( ( the ( floating ( platforms sink ) ) ) ( -LRB- ( ( Archimede law ) -RRB- ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN gas)) (VP (VBG arriving) (ADVP (RB quickly)) (PP (IN at) (NP (DT the) (NN surface))))) (VP (VBZ creates) (NP (NP (DT a) (ADJP (RB very) (JJ low)) (NN density) (NN fluid)) (CC and) (NP (NP (DT the) (VBG floating) (NNS platforms) (NN sink)) (PRN (-LRB- -LRB-) (NP (NNP Archimede) (NN law)) (-RRB- -RRB-))))) (. .)))
The gas arriving quickly at the surface creates a very low density fluid and the floating platforms sink (Archimede law).
(ROOT (S (NP (NP (NNP Archimedes) (POS ')) (NN law)) (VP (VBZ explains) (SBAR (WHADVP (WRB why)) (S (NP (NP (DT a) (NN ship)) (VP (VBG weighing) (NP (NP (NNS thousands)) (PP (IN of) (NP (JJ metric) (NNS tons)))))) (VP (VBZ floats) (PP (IN on) (NP (NN water))))))) (. .)))