( Tides ( ( are ( ( ( periodic fluctuations ) ( -LRB- ( ( ( rising and ) falling ) -RRB- ) ) ) ( of ( sea water ) ) ) ) . ) )
(ROOT (S (NP (NNS Tides)) (VP (VBP are) (NP (NP (JJ periodic) (NNS fluctuations)) (PRN (-LRB- -LRB-) (VP (VBG rising) (CC and) (VBG falling)) (-RRB- -RRB-)) (PP (IN of) (NP (NN sea) (NN water))))) (. .)))
Tides are periodic fluctuations (rising and falling) of sea water.
(ROOT (S (NP (NNS Tides)) (VP (VBZ is) (NP (NP (DT the) (NN term)) (PP (IN for) (SBAR (WHADVP (WRB when)) (S (NP (NP (DT the) (NN water)) (PP (IN of) (NP (DT the) (NN ocean)))) (ADVP (RB slowly)) (VP (VP (VBZ rises)) (CC and) (VP (VBZ falls)))))))) (. .)))