the three leads produce adequate performances , 
(ROOT (S (NP (DT the) (CD three) (NNS leads)) (VP (VBP produce) (NP (JJ adequate) (NNS performances))) (, ,)))
(ROOT (S (NP (DT ) (CD ) (NNS )) (VP (VBP ) (NP (JJ ) (NNS ))) (, )))