( ( Volcanic ( ( ash and ) Earth ) ) ( ( 's ( atmosphere 42 ) ) . ) )
(ROOT (S (NP (NNP Volcanic) (NNP ash) (CC and) (NNP Earth)) (VP (VBZ 's) (NP (NN atmosphere) (CD 42))) (. .)))
Volcanic ash and Earth's atmosphere 42.
(ROOT (S (NP (JJ Volcanic) (NNS gases)) (VP (VBP helpe) (S (VP (TO to) (VP (VB form) (NP (DT the) (NN atmosphere)) (PP (IN on) (NP (NN earth))))))) (. .)))