yeah i've always threatened to take lessons but i've never gotten around to it
( yeah ( ( ( i ( ( 've always ) ( threatened ( to ( take lessons ) ) ) ) ) but ) ( i ( ( 've never ) ( ( gotten around ) ( to it ) ) ) ) ) )
(ROOT (S (VP (VB yeah) (SBAR (S (S (NP (FW i)) (VP (VBP 've) (ADVP (RB always)) (VP (VBN threatened) (S (VP (TO to) (VP (VB take) (NP (NNS lessons)))))))) (CC but) (S (NP (FW i)) (VP (VBP 've) (ADVP (RB never)) (VP (VBN gotten) (PRT (RP around)) (PP (TO to) (NP (PRP it)))))))))))
I have been taking lessons for about fifteen years. 
( I ( ( have ( been ( taking ( lessons ( for ( about ( fifteen years ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP I)) (VP (VBP have) (VP (VBN been) (VP (VBG taking) (NP (NP (NNS lessons)) (PP (IN for) (NP (RB about) (CD fifteen) (NNS years))))))) (. .)))