( ( In ( ( each ( Lunar day ) ) ( of ( ( ( 24 hours ) and ) ( 51 minutes ) ) ) ) ) ( there ( ( ( ( are ( ( ( two ( high tides ) ) and ) ( two ( low tides ) ) ) ) , ) ( alternating ( at ( ( equal intervals ) ( of ( ( flood and ) ebb ) ) ) ) ) ) . ) ) )
(ROOT (S (PP (IN In) (NP (NP (DT each) (NNP Lunar) (NN day)) (PP (IN of) (NP (NP (CD 24) (NNS hours)) (CC and) (NP (CD 51) (NNS minutes)))))) (NP (EX there)) (VP (VBP are) (NP (NP (CD two) (JJ high) (NNS tides)) (CC and) (NP (CD two) (JJ low) (NNS tides))) (, ,) (S (VP (VBG alternating) (PP (IN at) (NP (NP (JJ equal) (NNS intervals)) (PP (IN of) (NP (NN flood) (CC and) (NN ebb)))))))) (. .)))
In each Lunar day of 24 hours and 51 minutes there are two high tides and two low tides, alternating at equal intervals of flood and ebb.
(ROOT (S (NP (NP (CD Two) (NN low)) (CC and) (NP (JJ high) (NNS tides))) (VP (VBP occur) (PP (IN per) (NP (NN day)))) (. .)))