( ( ( ( The atoms ) ( in ( the ( gas ( ( collide and ) heat ) ) ) ) ) up ) ( , ( ( ( ( ( the heat ) ( is ( radiated ( in ( the ( infrared ( -LRB- ( light -RRB- ) ) ) ) ) ) ) ) and ) ( ( the result ) ( is ( ( the gas ) ( ( ( loses energy ) , ) ( moves ( ( slowly ( = collapses ) ) ( to ( the center ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (ADVP (NP (NP (DT The) (NNS atoms)) (PP (IN in) (NP (DT the) (NN gas) (NN collide) (CC and) (NN heat)))) (RB up)) (, ,) (S (NP (DT the) (NN heat)) (VP (VBZ is) (VP (VBN radiated) (PP (IN in) (NP (DT the) (JJ infrared) (-LRB- -LRB-) (NN light) (-RRB- -RRB-)))))) (CC and) (S (NP (DT the) (NN result)) (VP (VBZ is) (NP (NP (DT the) (NN gas)) (SBAR (S (VP (VBZ loses) (NP (NN energy)) (, ,) (NP (NP (NNS moves)) (ADVP (RB slowly) (NP (CD =) (NNS collapses)) (PP (TO to) (NP (DT the) (NN center))))))))))) (. .)))
The atoms in the gas collide and heat up, the heat is radiated in the infrared (light) and the result is the gas loses energy, moves slowly = collapses to the center.
(ROOT (S (PP (IN Within) (NP (DT a) (NN substance))) (, ,) (NP (NP (NNS atoms)) (SBAR (WHNP (WDT that)) (S (VP (VP (VBP collide) (ADVP (RB frequently))) (CC and) (VP (VBP move) (ADVP (RB independently)) (PP (IN of) (NP (CD one) (DT another)))))))) (VP (VBP are) (ADJP (ADJP (RBS most) (JJ likely)) (PP (IN in) (NP (DT a) (NN gas)))))))