( ( ( Used ( motor oil ) ) ( when ( disposed ( of ( to ( ( ( the sewer ) or ) ( the ( storm drain ) ) ) ) ) ) ) ) ( ( can ( be ( bad ( for ( the environment ) ) ) ) ) . ) )
(ROOT (S (NP (NP (JJ Used) (NN motor) (NN oil)) (SBAR (WHADVP (WRB when)) (S (VP (VBN disposed) (PP (IN of) (PP (TO to) (NP (NP (DT the) (NN sewer)) (CC or) (NP (DT the) (NN storm) (NN drain))))))))) (VP (MD can) (VP (VB be) (ADJP (JJ bad) (PP (IN for) (NP (DT the) (NN environment)))))) (. .)))
Used motor oil when disposed of to the sewer or the storm drain can be bad for the environment.
(ROOT (S (NP (NNP Motor) (NN oil)) (VP (VBZ is) (NP (NP (DT a) (JJ harmful) (NN substance)) (SBAR (WHNP (WDT that)) (S (VP (MD must) (RB not) (VP (VB be) (VP (VBN drained) (PP (IN into) (NP (DT a) (NN storm) (NN sewer)))))))))) (. .)))