( ( By contrast ) ( , ( ( going ( after ( the ( many ( clean cars ) ) ) ) ) ( ( ( will likely ) ( ( ( cost ( ( a lot ) ( of money ) ) ) and ) ( yield ( minimal ( air ( quality improvements ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN By) (NP (NN contrast))) (, ,) (S (VP (VBG going) (PP (IN after) (NP (DT the) (JJ many) (JJ clean) (NNS cars))))) (VP (MD will) (ADVP (RB likely)) (VP (VP (VB cost) (NP (NP (DT a) (NN lot)) (PP (IN of) (NP (NN money))))) (CC and) (VP (VB yield) (NP (JJ minimal) (NN air) (NN quality) (NNS improvements))))) (. .)))
By contrast, going after the many clean cars will likely cost a lot of money and yield minimal air quality improvements.
(ROOT (S (S (VP (VBG Limiting) (NP (NP (DT the) (NN number)) (PP (IN of) (NP (NP (NNS cars)) (PP (IN on) (NP (DT the) (NNS roads)))))))) (VP (MD would) (ADVP (RBS most) (RB likely)) (VP (VB improve) (NP (DT the) (NN air) (NN quality)) (PP (IN in) (NP (JJ large) (NNS texas) (NNS cities))))) (. .)))