( ( The class ) ( ( will ( be ( divided ( into ( ( seven groups ) ( of three ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN class)) (VP (MD will) (VP (VB be) (VP (VBN divided) (PP (IN into) (NP (NP (CD seven) (NNS groups)) (PP (IN of) (NP (CD three)))))))) (. .)))
The class will be divided into seven groups of three.
(ROOT (S (NP (NNS Mollusks)) (VP (MD can) (VP (VB be) (VP (VBN divided) (PP (IN into) (NP (CD seven) (NNS classes)))))) (. .)))
Mollusks can be divided into seven classes.