forced to watch him try out so many complicated facial expressions 
(ROOT (VP (VBN forced) (S (VP (TO to) (VP (VB watch) (S (NP (PRP him)) (VP (VB try) (PRT (RP out)) (NP (ADJP (RB so) (JJ many)) (JJ complicated) (JJ facial) (NNS expressions)))))))))
(ROOT (VP (VBN ) (S (VP (TO ) (VP (VB ) (S (NP (PRP )) (VP (VB ) (PRT (RP )) (NP (ADJP (RB ) (JJ )) (JJ ) (JJ ) (NNS )))))))))