( ( In ( ( ( some materials ) , ) ( called superconductors ) ) ) ( , ( resistance ( ( decreases ( to ( zero ( at ( ( critically low ) temperature ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NP (DT some) (NNS materials)) (, ,) (NP (VBN called) (NNS superconductors)))) (, ,) (NP (NN resistance)) (VP (VBZ decreases) (S (VP (TO to) (VP (VB zero) (PP (IN at) (NP (ADJP (RB critically) (JJ low)) (NN temperature))))))) (. .)))
In some materials, called superconductors, resistance decreases to zero at critically low temperature.
(ROOT (S (NP (NNS Superconductors)) (VP (VBP are) (NP (NP (NNS materials)) (PP (IN with) (NP (NP (DT a) (NN resistivity)) (PP (IN of) (NP (CD zero))))))) (. .)))