( ( Under ( ( conditions ( of ( high ( ( temperature and ) pressure ) ) ) ) ( in ( the ( combustion chamber ) ) ) ) ) ( , ( nitrogen ( ( can ( ( combine ( with oxygen ) ) ( to ( form ( ( harmful oxides ) ( of ( nitrogen ( -LRB- ( NOx -RRB- ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN Under) (NP (NP (NNS conditions)) (PP (IN of) (NP (JJ high) (NN temperature) (CC and) (NN pressure))) (PP (IN in) (NP (DT the) (NN combustion) (NN chamber))))) (, ,) (NP (NN nitrogen)) (VP (MD can) (VP (VB combine) (PP (IN with) (NP (NN oxygen))) (S (VP (TO to) (VP (VB form) (NP (NP (JJ harmful) (NNS oxides)) (PP (IN of) (NP (NP (NN nitrogen)) (PRN (-LRB- -LRB-) (NP (NNP NOx)) (-RRB- -RRB-)))))))))) (. .)))
Under conditions of high temperature and pressure in the combustion chamber, nitrogen can combine with oxygen to form harmful oxides of nitrogen (NOx).
(ROOT (S (NP (NNP Nitrogen)) (VP (VBZ oxide) (NP (NP (NN form)) (PRN (-LRB- -LRB-) (PRP s) (-RRB- -RRB-)) (SBAR (WHADVP (WRB when)) (S (NP (NN nitrogen) (CC and) (NN oxygen)) (VP (VBP combine) (PP (IN at) (NP (JJ high) (NNS temperatures)))))))) (. .)))