( ( The picture ) ( ( shows ( ( the ( gas density ) ) ( -LRB- ( ( ( ( ( ( a ( logarithmic plot ) ) , ) ( red ( represents ( high density ) ) ) ) , ) ( blue ( represents ( low density ) ) ) ) -RRB- ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN picture)) (VP (VBZ shows) (NP (NP (DT the) (NN gas) (NN density)) (PRN (-LRB- -LRB-) (NP (NP (DT a) (JJ logarithmic) (NN plot)) (, ,) (NP (JJ red) (JJ represents) (JJ high) (NN density)) (, ,) (NP (JJ blue) (JJ represents) (JJ low) (NN density))) (-RRB- -RRB-)))) (. .)))
The picture shows the gas density (a logarithmic plot, red represents high density, blue represents low density).
(ROOT (S (NP (NNS Gases)) (VP (VBP have) (NP (DT the) (JJS lowest) (NN density))) (. .)))