( ( ( ( ( ( The ( electric energy ) ) ( used ( by ( an appliance ) ) ) ) , ) ( measured ( in ( kiloWatt-hours ( -LRB- ( kWh -RRB- ) ) ) ) ) ) , ) ( ( is ( ( ( ( the product ) ( of ( its ( average ( power requirement ) ) ) ) ) and ) ( ( the amount ) ( of ( time ( it operates ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ electric) (NN energy)) (VP (VBN used) (PP (IN by) (NP (DT an) (NN appliance)))) (, ,) (VP (VBN measured) (PP (IN in) (NP (NP (NNS kiloWatt-hours)) (PRN (-LRB- -LRB-) (NP (NN kWh)) (-RRB- -RRB-))))) (, ,)) (VP (VBZ is) (NP (NP (NP (DT the) (NN product)) (PP (IN of) (NP (PRP$ its) (JJ average) (NN power) (NN requirement)))) (CC and) (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NP (NN time)) (SBAR (S (NP (PRP it)) (VP (VBZ operates))))))))) (. .)))
The electric energy used by an appliance, measured in kiloWatt-hours (kWh) , is the product of its average power requirement and the amount of time it operates.
(ROOT (S (NP (NP (JJ Electrical) (NN energy)) (VP (VBN consumed))) (VP (MD can) (VP (VB be) (VP (VBN expressed) (PP (IN as) (NP (NP (DT the) (NN product)) (PP (IN of) (NP (NP (NN power)) (VP (VBN multiplied) (PP (IN by) (NP (NN time))))))))))) (. .)))