( Volts ( ( are ( ( a measure ) ( of ( electric potential ) ) ) ) . ) )
(ROOT (S (NP (NNS Volts)) (VP (VBP are) (NP (NP (DT a) (NN measure)) (PP (IN of) (NP (JJ electric) (NN potential))))) (. .)))
Volts are a measure of electric potential.
(ROOT (S (NP (NP (DT The) (NN difference)) (PP (IN in) (NP (NP (JJ electric) (JJ potential) (NN energy)) (SBAR (WHNP (WDT which)) (S (VP (VBZ allows) (PP (IN for) (NP (DT an) (JJ electric) (NN charge))) (S (VP (TO to) (VP (VB move) (PP (IN from) (NP (CD one) (NN position))) (PP (TO to) (NP (DT another)))))))))))) (VP (VBZ is) (VP (VBN measured) (PP (IN by) (NP (DT the) (JJ volt) (NN si) (NN unit))))) (. .)))