( ( Oxygen concentrators ) ( ( ( are also ) ( used ( to ( ( ( ( provide ( ( an ( economical source ) ) ( of oxygen ) ) ) ( in ( industrial processes ) ) ) , ) ( where ( they ( ( are also ) ( known ( as ( ( ( Oxygen ( Gas Generators ) ) or ) ( Oxygen ( Generation Plants ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NN Oxygen) (NNS concentrators)) (VP (VBP are) (ADVP (RB also)) (VP (VBN used) (S (VP (TO to) (VP (VB provide) (NP (NP (DT an) (JJ economical) (NN source)) (PP (IN of) (NP (NN oxygen)))) (PP (IN in) (NP (JJ industrial) (NNS processes))) (, ,) (SBAR (WHADVP (WRB where)) (S (NP (PRP they)) (VP (VBP are) (ADVP (RB also)) (VP (VBN known) (PP (IN as) (NP (NP (NNP Oxygen) (NNP Gas) (NNP Generators)) (CC or) (NP (NNP Oxygen) (NNP Generation) (NNP Plants))))))))))))) (. .)))
Oxygen concentrators are also used to provide an economical source of oxygen in industrial processes, where they are also known as Oxygen Gas Generators or Oxygen Generation Plants.
(ROOT (S (NP (NN Oxygen) (NN gas)) (VP (VBZ is) (VP (VBN given) (PRT (RP off)) (PP (IN by) (NP (NNS plants))))) (. .)))