( ( ( ( ( Many lizards ) ( display ( four limbs ) ) ) but ) ( there ( are ( ( certain ( skink species ) ) ( that ( are ( completely limbless ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (JJ Many) (NNS lizards)) (VP (VBP display) (NP (CD four) (NNS limbs)))) (CC but) (S (NP (EX there)) (VP (VBP are) (NP (NP (JJ certain) (NN skink) (NNS species)) (SBAR (WHNP (WDT that)) (S (VP (VBP are) (ADJP (RB completely) (JJ limbless)))))))) (. .)))
Many lizards display four limbs but there are certain skink species that are completely limbless.
(ROOT (S (NP (NNP Birds)) (VP (VBP have) (NP (CD four) (NNS limbs))) (. .)))