convince us of that all on their own 
(ROOT (VP (VB convince) (NP (PRP us)) (PP (IN of) (NP (DT that))) (PP (ADVP (DT all)) (IN on) (NP (PRP$ their) (JJ own)))))
(ROOT (VP (VB ) (NP (PRP )) (PP (IN ) (NP (DT ))) (PP (ADVP (DT )) (IN ) (NP (PRP$ ) (JJ )))))