Julius nodded gravely.
( Julius ( ( nodded gravely ) . ) )
(ROOT (S (NP (NNP Julius)) (VP (VBD nodded) (ADVP (RB gravely))) (. .)))
Julius nodded solemnly. 
( Julius ( ( nodded solemnly ) . ) )
(ROOT (S (NP (NNP Julius)) (VP (VBD nodded) (ADVP (RB solemnly))) (. .)))