( Group ( -LRB- ( ( periodic table ) -RRB- ) ) )
(ROOT (NP (NP (NNP Group)) (PRN (-LRB- -LRB-) (NP (JJ periodic) (NN table)) (-RRB- -RRB-))))
Group (periodic table)
(ROOT (S (NP (NP (NNP Group) (CD 13)) (PP (IN of) (NP (DT the) (JJ periodic) (NN table)))) (VP (VBZ is) (ADVP (RB also)) (VP (VBN called) (NP (DT the) (DT the) (NN boron) (NN group)))) (. .)))