How old would you say you were when your cousins were doing this reading?
( ( How old ) ( ( ( would you ) ( say ( you ( were ( when ( ( your cousins ) ( were ( doing ( this reading ) ) ) ) ) ) ) ) ) ? ) )
(ROOT (SBARQ (WHADJP (WRB How) (JJ old)) (SQ (MD would) (NP (PRP you)) (VP (VB say) (SBAR (S (NP (PRP you)) (VP (VBD were) (SBAR (WHADVP (WRB when)) (S (NP (PRP$ your) (NNS cousins)) (VP (VBD were) (VP (VBG doing) (NP (DT this) (NN reading))))))))))) (. ?)))
What was your age when your cousins read this? 
( What ( ( was ( ( your age ) ( when ( ( your cousins ) ( read this ) ) ) ) ) ? ) )
(ROOT (SBARQ (WHNP (WP What)) (SQ (VBD was) (NP (NP (PRP$ your) (NN age)) (SBAR (WHADVP (WRB when)) (S (NP (PRP$ your) (NNS cousins)) (VP (VBP read) (NP (DT this))))))) (. ?)))