( ( If ( ( the ( greenhouse ( gas tax ) ) ) ( grew ( over time ) ) ) ) ( it ( ( might ( ( trigger ( a ( complete shift ) ) ) ( to ( ( renewable ( ( ( energy sources ) and ) ( ( the adoption ) ( of ( effective measures ) ) ) ) ) ( to ( reduce ( ( the need ) ( for energy ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (SBAR (IN If) (S (NP (DT the) (NN greenhouse) (NN gas) (NN tax)) (VP (VBD grew) (PP (IN over) (NP (NN time)))))) (NP (PRP it)) (VP (MD might) (VP (VB trigger) (NP (DT a) (JJ complete) (NN shift)) (S (VP (TO to) (VP (VB renewable) (NP (NP (NN energy) (NNS sources)) (CC and) (NP (NP (DT the) (NN adoption)) (PP (IN of) (NP (JJ effective) (NNS measures))))) (S (VP (TO to) (VP (VB reduce) (NP (NP (DT the) (NN need)) (PP (IN for) (NP (NN energy)))))))))))) (. .)))
If the greenhouse gas tax grew over time it might trigger a complete shift to renewable energy sources and the adoption of effective measures to reduce the need for energy.
(ROOT (S (NP (JJ Renewable) (NN energy) (NNS sources)) (VP (VBP emit) (NP (NP (JJR fewer)) (CC or) (NP (DT no) (NN greenhouse) (NNS gases)))) (. .)))