( ( ( atoms , ) ( isotopes ( , ( elements ( , ( ( ions and ) compounds ) ) ) ) ) ) ; )
(ROOT (NP (NP (NNS atoms)) (, ,) (NP (NNS isotopes) (, ,) (NNS elements) (, ,) (NNS ions) (CC and) (NNS compounds)) (: ;)))
atoms, isotopes, elements, ions and compounds;
(ROOT (S (NP (NP (JJ Ionic) (NN compound) (NNS atoms)) (PP (IN of) (NP (JJ various) (NNS elements)))) (VP (VBP gain) (CC or) (VBP lose) (NP (NNS electrons) (S (VP (TO to) (VP (VB produce) (NP (NNS ions))))))) (. .)))