watch them go about their daily activities for two whole hours 
(ROOT (S (VP (VB watch) (S (NP (PRP them)) (VP (VB go) (PP (IN about) (NP (PRP$ their) (JJ daily) (NNS activities))) (PP (IN for) (NP (CD two) (JJ whole) (NNS hours))))))))
(ROOT (S (VP (VB ) (S (NP (PRP )) (VP (VB ) (PP (IN ) (NP (PRP$ ) (JJ ) (NNS ))) (PP (IN ) (NP (CD ) (JJ ) (NNS ))))))))