( ( Human beings ) ( ( ( can only ) ( visualize ( in ( three dimensions ) ) ) ) . ) )
(ROOT (S (NP (NNP Human) (NNS beings)) (VP (MD can) (ADVP (RB only)) (VP (VB visualize) (PP (IN in) (NP (CD three) (NNS dimensions))))) (. .)))
Human beings can only visualize in three dimensions.
(ROOT (S (NP (NNS Humans)) (VP (MD can) (VP (VB see) (PP (IN in) (NP (CD three) (NNS dimensions))))) (. .)))