Generally, FGD systems tend to be constructed closer to the ground compared to SCR technology retrofits.
( Generally ( , ( ( FGD systems ) ( ( tend ( to ( be ( ( constructed ( closer ( to ( the ground ) ) ) ) ( compared ( to ( SCR ( technology retrofits ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (ADVP (RB Generally)) (, ,) (NP (NNP FGD) (NNS systems)) (VP (VBP tend) (S (VP (TO to) (VP (VB be) (VP (VBN constructed) (ADVP (RBR closer) (PP (TO to) (NP (DT the) (NN ground)))) (PP (VBN compared) (PP (TO to) (NP (NNP SCR) (NN technology) (NNS retrofits))))))))) (. .)))
FGD systems tend to replicate SCR systems.
( ( FGD systems ) ( ( tend ( to ( ( replicate SCR ) systems ) ) ) . ) )
(ROOT (S (NP (NNP FGD) (NNS systems)) (VP (VBP tend) (S (VP (TO to) (VP (VB replicate) (NP (NNP SCR)) (NP (NNS systems)))))) (. .)))