( ( Pressure increases ) ( ( rapidly ( ( ( ( under water ) , ) and ) ( at ( ( ( 10 metres ) ( -LRB- ( 30ft -RRB- ) ) ) ( ( depth , ) pressure ) ) ) ) ) ( ( ( is double ) ( that ( at ( the surface ) ) ) ) . ) ) )
(ROOT (S (NP (NN Pressure) (NNS increases)) (ADVP (RB rapidly) (PP (PP (IN under) (NP (NN water))) (, ,) (CC and) (PP (IN at) (NP (NP (NP (CD 10) (NNS metres)) (PRN (-LRB- -LRB-) (NP (NNP 30ft)) (-RRB- -RRB-))) (NP (NP (NN depth)) (, ,) (NP (NN pressure))))))) (VP (VBZ is) (RB double) (NP (NP (DT that)) (PP (IN at) (NP (DT the) (NN surface))))) (. .)))
Pressure increases rapidly under water, and at 10 metres (30ft) depth, pressure is double that at the surface.
(ROOT (S (NP (NP (DT The) (NN pressure)) (PP (IN of) (NP (NN ocean) (NN water)))) (VP (VBZ increases) (ADVP (RB rapidly)) (SBAR (IN as) (S (NP (DT the) (NN water)) (VP (VBZ gets) (ADVP (RBR deeper)))))) (. .)))