( There ( ( are ( ( six types ) ( of ( ( leptons and ) quarks ) ) ) ) . ) )
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD six) (NNS types)) (PP (IN of) (NP (NNS leptons) (CC and) (NNS quarks))))) (. .)))
There are six types of leptons and quarks.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD six) (NNS types)) (PP (IN of) (NP (NNS leptons))))) (. .)))