( ( ( ( Alternating Current ) ( -LRB- ( AC -RRB- ) ) ) ( ( A current ) ( that ( ( flows alternately ) ( in ( ( ( one direction ) and ) ( then ( in ( the ( reverse direction ) ) ) ) ) ) ) ) ) ) . )
(ROOT (NP (NP (NP (VBG Alternating) (NNS Current)) (PRN (-LRB- -LRB-) (NP (NNP AC)) (-RRB- -RRB-))) (NP (NP (DT A) (NN current)) (SBAR (WHNP (WDT that)) (S (VP (VBZ flows) (ADVP (RB alternately)) (PP (IN in) (NP (NP (CD one) (NN direction)) (CC and) (NP (NP (RB then)) (PP (IN in) (NP (DT the) (JJ reverse) (NN direction)))))))))) (. .)))
Alternating Current (AC) A current that flows alternately in one direction and then in the reverse direction.
(ROOT (S (NP (VBG Alternating) (NN current)) (VP (VBZ is) (NP (NP (DT the) (NN term)) (PP (IN for) (NP (JJ electric) (NN current))) (SBAR (WHNP (WDT that)) (S (VP (VBZ keeps) (S (VP (VBG reversing) (NP (NN direction))))))))) (. .)))