(S (S (S (NP (BASENP (NNP TransCanada)) (PRN (COMMA ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ owns) (BASENP (DT the) (NN pipeline))))) (COMMA ,))) (VP (VBD stopped) (BASENP (NN construction)))) (SBAR (IN once) (S (BASENP (DT the) (NN protest)) (VP (VBD began))))) (PERIOD .))