( ( Geothermal ( power plants ) ) ( ( ( use ( ( the ( Earth 's ) ) ( natural ( underground heat ) ) ) ) ( to ( provide ( ( clean ( , renewable ) ) energy ) ) ) ) . ) )
(ROOT (S (NP (JJ Geothermal) (NN power) (NNS plants)) (VP (VBP use) (NP (NP (DT the) (NN Earth) (POS 's)) (JJ natural) (JJ underground) (NN heat)) (S (VP (TO to) (VP (VB provide) (NP (ADJP (JJ clean) (, ,) (JJ renewable)) (NN energy)))))) (. .)))
Geothermal power plants use the Earth's natural underground heat to provide clean, renewable energy.
(ROOT (S (NP (JJ Geothermal) (NN power)) (VP (VBZ is) (VP (VBN generated) (PP (IN via) (NP (NP (JJ underground) (NNS sources)) (PP (IN of) (NP (NN heat))))))) (. .)))
Geothermal power is generated via underground sources of heat.