( ( These metals ) ( ( ( ( are ( called ( alkali metals ) ) ) and ) ( belong ( to ( ( group I ) ( of ( the ( periodic table ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT These) (NNS metals)) (VP (VP (VBP are) (VP (VBN called) (NP (JJ alkali) (NNS metals)))) (CC and) (VP (VBP belong) (PP (TO to) (NP (NP (NN group) (NN I)) (PP (IN of) (NP (DT the) (JJ periodic) (NN table))))))) (. .)))
These metals are called alkali metals and belong to group I of the 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)))) (. .)))