( ( ( ( ( Some ( of ( these substances ) ) ) ( can burn ) ) - ) ( ( for example ) ( , ( ( organic lead ) ( compounds ( in ( some gasolines ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (NP (DT Some)) (PP (IN of) (NP (DT these) (NNS substances)))) (VP (MD can) (VP (VB burn)))) (: -) (S (PP (IN for) (NP (NN example))) (, ,) (NP (JJ organic) (NN lead)) (VP (VBZ compounds) (PP (IN in) (NP (DT some) (NNS gasolines))))) (. .)))
Some of these substances can burn - for example, organic lead compounds in some gasolines.
(ROOT (S (NP (NNP Wood) (NNP burning)) (VP (VBZ is) (NP (NP (DT an) (NN example)) (PP (IN of) (NP (NP (DT a) (JJ different) (NN substance)) (VP (VBG being) (VP (VBN formed))))))) (. .)))