( ( ( ( ( Tidal power ) , ) ( also ( called ( tidal energy ) ) ) ) , ) ( ( is ( ( ( a form ) ( of hydropower ) ) ( that ( ( converts ( ( the energy ) ( of tides ) ) ) ( into ( ( useful forms ) ( of ( ( ( power , ) mainly ) electricity ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (JJ Tidal) (NN power)) (, ,) (VP (ADVP (RB also)) (VBN called) (NP (JJ tidal) (NN energy))) (, ,)) (VP (VBZ is) (NP (NP (DT a) (NN form)) (PP (IN of) (NP (NN hydropower))) (SBAR (WHNP (WDT that)) (S (VP (VBZ converts) (NP (NP (DT the) (NN energy)) (PP (IN of) (NP (NNS tides)))) (PP (IN into) (NP (NP (JJ useful) (NNS forms)) (PP (IN of) (NP (NP (NN power)) (, ,) (RB mainly) (NP (NN electricity))))))))))) (. .)))
Tidal power, also called tidal energy, is a form of hydropower that converts the energy of tides into useful forms of power, mainly electricity.
(ROOT (S (NP (NNP Hydropower)) (VP (VBZ is) (NP (NP (DT the) (ADJP (RBS most) (RB widely) (VBN used)) (NN form)) (PP (IN of) (NP (NP (JJ renewable) (NN energy)) (PP (IN in) (NP (DT the) (NN world))))))) (. .)))