Who? asked Tommy.
( ( ( Who ? ) ( asked Tommy ) ) . )
(ROOT (S (S (FRAG (WHNP (WP Who)) (. ?)) (NP (JJ asked)) (VP (VBZ Tommy))) (. .)))
Tommy inquired about the identity of the person.
( Tommy ( ( inquired ( about ( ( the identity ) ( of ( the person ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Tommy)) (VP (VBD inquired) (PP (IN about) (NP (NP (DT the) (NN identity)) (PP (IN of) (NP (DT the) (NN person)))))) (. .)))