It vibrated under his hand.
( It ( ( vibrated ( under ( his hand ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBD vibrated) (PP (IN under) (NP (PRP$ his) (NN hand)))) (. .)))
It hummed quietly in his hand.
( It ( ( ( hummed quietly ) ( in ( his hand ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBD hummed) (ADVP (RB quietly)) (PP (IN in) (NP (PRP$ his) (NN hand)))) (. .)))