( Elements ( ( are ( ( pure substances ) ( that ( ( ( have ( ( a set ) ( of ( unique properties ) ) ) ) and ) ( ( can not ) ( be ( ( ( further ( broken down ) ) or ) ( ( decomposed ( into ( other elements ) ) ) ( by ( chemical methods ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Elements)) (VP (VBP are) (NP (NP (JJ pure) (NNS substances)) (SBAR (WHNP (WDT that)) (S (VP (VP (VBP have) (NP (NP (DT a) (NN set)) (PP (IN of) (NP (JJ unique) (NNS properties))))) (CC and) (VP (MD can) (RB not) (VP (VB be) (VP (VP (ADVP (RBR further)) (VBN broken) (PRT (RP down))) (CC or) (VP (VBN decomposed) (PP (IN into) (NP (JJ other) (NNS elements))) (PP (IN by) (NP (NN chemical) (NNS methods)))))))))))) (. .)))
Elements are pure substances that have a set of unique properties and cannot be further broken down or decomposed into other elements by chemical methods.
(ROOT (S (NP (NP (NNS Substances)) (SBAR (WHNP (WDT that)) (S (VP (MD can) (RB not) (VP (VB be) (VP (VBN broken) (PRT (RP down)) (PP (IN into) (NP (NP (JJR simpler) (NNS substances)) (PP (IN with) (NP (JJ different) (NNS properties))))))))))) (VP (VBP are) (VP (VBN called) (NP (NNS elements)))) (. .)))