Why, when I was your age, I already had...."  Dave wasn't listening any longer.
( Why ( , ( ( ( ( ( ( when ( I ( was ( your age ) ) ) ) ( , ( I ( already had ) ) ) ) ... ) '' ) ( Dave ( ( was n't ) ( listening ( any longer ) ) ) ) ) . ) ) )
(ROOT (S (ADVP (WRB Why)) (, ,) (S (SBAR (WHADVP (WRB when)) (S (NP (PRP I)) (VP (VBD was) (NP (PRP$ your) (NN age))))) (, ,) (NP (PRP I)) (ADVP (RB already)) (VP (VBD had))) (: ...) ('' '') (S (NP (NNP Dave)) (VP (VBD was) (RB n't) (VP (VBG listening) (ADVP (DT any) (RBR longer))))) (. .)))
The conversation was one Dave had heard hundreds of times. 
( ( The conversation ) ( ( was ( one ( Dave ( had ( heard ( hundreds ( of times ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN conversation)) (VP (VBD was) (NP (NP (CD one)) (SBAR (S (NP (NNP Dave)) (VP (VBD had) (VP (VBN heard) (NP (QP (NNS hundreds) (IN of) (NNS times))))))))) (. .)))