( ( ( The ( group numbers ) ) ( of ( the ( nonmetal elements ) ) ) ) ( ( indicate ( ( their ( total number ) ) ( of ( valence electrons ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN group) (NNS numbers)) (PP (IN of) (NP (DT the) (JJ nonmetal) (NNS elements)))) (VP (VBP indicate) (NP (NP (PRP$ their) (JJ total) (NN number)) (PP (IN of) (NP (JJ valence) (NNS electrons))))) (. .)))
The group numbers of the nonmetal elements indicate their total number of valence electrons.
(ROOT (S (NP (NNS Nonmetals)) (VP (VBP have) (NP (NP (DT the) (JJS highest) (NN attraction)) (PP (IN for) (NP (NNS electrons))))) (. .)))