( ( ( the ability ) ( of ( a ( material ( to ( resist ( ( the flow ) ( of ( electric current ) ) ) ) ) ) ) ) ) . )
(ROOT (NP (NP (DT the) (NN ability)) (PP (IN of) (NP (DT a) (NN material) (S (VP (TO to) (VP (VB resist) (NP (NP (DT the) (NN flow)) (PP (IN of) (NP (JJ electric) (NN current))))))))) (. .)))
the ability of a material to  resist the flow of electric current.
(ROOT (S (NP (PRP You)) (VP (VBP call) (NP (NP (NNS materials)) (SBAR (WHNP (WDT that)) (S (VP (VBP have) (NP (JJ high) (NN resistance)) (PP (TO to) (NP (JJ electric) (JJ current) (JJ electric) (NNS insulators)))))))) (. .)))