is actually one of its strengths . 
(ROOT (S (VP (VBZ is) (ADVP (RB actually)) (NP (NP (CD one)) (PP (IN of) (NP (PRP$ its) (NNS strengths))))) (. .)))
(ROOT (S (VP (VBZ ) (ADVP (RB )) (NP (NP (CD )) (PP (IN ) (NP (PRP$ ) (NNS ))))) (. )))