( ( 5 ( Typical ( ion ( gas laser ) ) ) ) ( ( -LRB- ( 18 -RRB- ) ) ( ( The ( ballast tank ) ) ( ( ( ( provides ( ( a source ) ( of gas ) ) ) ( -LRB- ( ( ( connected ( to ( the ( plasma tube ) ) ) ) ( by ( a valve ) ) ) -RRB- ) ) ) ( to ( ( maintain ( the tube ) ) ( at ( optimum ( operating pressure ) ) ) ) ) ) . ) ) ) )
(ROOT (S (NP (CD 5) (JJ Typical) (NNP ion) (NN gas) (NN laser)) (PRN (-LRB- -LRB-) (NP (CD 18)) (-RRB- -RRB-)) (NP (DT The) (NN ballast) (NN tank)) (VP (VBZ provides) (NP (NP (DT a) (NN source)) (PP (IN of) (NP (NN gas)))) (PRN (-LRB- -LRB-) (VP (VBN connected) (PP (TO to) (NP (DT the) (NN plasma) (NN tube))) (PP (IN by) (NP (DT a) (NN valve)))) (-RRB- -RRB-)) (S (VP (TO to) (VP (VB maintain) (NP (DT the) (NN tube)) (PP (IN at) (NP (JJ optimum) (NN operating) (NN pressure))))))) (. .)))
5 Typical ion gas laser (18) The ballast tank provides a source of gas (connected to the plasma tube by a valve) to maintain the tube at optimum operating pressure.
(ROOT (S (NP (NNP Plasma)) (VP (VBZ is) (NP (NP (DT the) (NN state)) (PP (IN of) (NP (NN matter))) (SBAR (WHNP (WDT that)) (S (VP (VP (VBZ resembles) (NP (DT a) (NN gas))) (, ,) (CC but) (VP (VBZ is) (VP (VBN made) (PP (IN of) (NP (NNS ions))) (, ,) (S (VP (VBG giving) (NP (PRP it)) (NP (NP (JJ different) (NNS properties)) (PP (IN than) (NP (DT a) (JJ typical) (NN gas))))))))))))) (. .)))