( ( at ( ( ( the bottom ) ( of ( the ocean ) ) ) ( where ( ( the ( in ( the great ) ) ) deep ) ) ) ) ( there ( ( is ( total darkness ) ) . ) ) )
(ROOT (S (PP (IN at) (NP (NP (DT the) (NN bottom)) (PP (IN of) (NP (DT the) (NN ocean))) (SBAR (WHADVP (WRB where)) (S (NP (NP (DT the)) (PP (IN in) (NP (DT the) (JJ great)))) (ADJP (JJ deep)))))) (NP (EX there)) (VP (VBZ is) (NP (JJ total) (NNS darkness))) (. .)))
at the bottom of the ocean where the in the great deep there is total darkness.
(ROOT (S (NP (JJ Deep) (NNS currents)) (VP (VBP are) (VP (VBN caused) (PP (IN by) (NP (NP (NNS differences)) (PP (IN in) (NP (NN density))))) (PP (IN at) (NP (NP (DT the) (NN top) (CC and) (NN bottom)) (PP (IN of) (NP (DT the) (NN ocean))))))) (. .)))