He sat up, trying to free himself.
( He ( ( ( ( sat up ) , ) ( trying ( to ( free himself ) ) ) ) . ) )
(ROOT (S (NP (PRP He)) (VP (VBD sat) (PRT (RP up)) (, ,) (S (VP (VBG trying) (S (VP (TO to) (VP (VB free) (NP (PRP himself)))))))) (. .)))
He was trying to take a nap.
( He ( ( was ( trying ( to ( take ( a nap ) ) ) ) ) . ) )
(ROOT (S (NP (PRP He)) (VP (VBD was) (VP (VBG trying) (S (VP (TO to) (VP (VB take) (NP (DT a) (NN nap))))))) (. .)))