that one viewing ca n't possibly be enough 
(ROOT (SBAR (IN that) (S (NP (CD one) (NN viewing)) (VP (MD ca) (RB n't) (ADVP (RB possibly)) (VP (VB be) (ADJP (JJ enough)))))))
(ROOT (SBAR (IN ) (S (NP (CD ) (NN )) (VP (MD ) (RB ) (ADVP (RB )) (VP (VB ) (ADJP (JJ )))))))